



' t v • • - v * .- 

/' .1 u . ' • . 


• \ '■ *' ’• <>( 

dnit4 

■i; b-: p 

•O . 

b yOv-- 


mpB i 

Maiiji 

bvv-x 

j.-'t. i.\< 

* • •■ufH 
k«.; vb'-; 


C 5 < 


Rffifl 


mm 

I® 

■illS] 

ill'll 
ill! 


irni 


St!.-: 


fbi, i *<: t 7 























































































































































































































































































































































































































































* rt 

% *’* V s %’ * •* '> 

4 ^'. .v. A 



« °o o°‘ .\ir *<• 

*'| ■’bo' f. 

; s / 





^ ■ /■ 

* % ^ c 6 % . 

^ m'\^’ ^ 

° A^ ^ ° fW, >' 

. ^ * . * 0 - 

“■ •* ''o Q^' ° ZJ^, 

>« ^ •* " 

<A * '■''AVVOf* ^ \ V A, 

' .rp c >, ** .. ' .'*'' j«P A. l. 



K 0c U 




















A *' 




'Ac.* s f ‘° ' v' 




* V 1 

4 * oV * % 

* M 



® *?> 

A> * 

* 0 /c« N ^/lp^ S /\. 

C> * cJ^Vv „ <*■ 'P A v V 

u <*. <AnS\\iv 4 _ ^ ^ \\ * 

▼ * 

A o, 

S A /<• / 

A+ ■ b* '- ('*' ,* C\ .» - »- 

<S >. *«!'>” 4 ° s , . °,2 'ill’ ^ 

. - vA'WaA c * v x 

A A * 




•fe A * 

1 - o 'S'V A> o 


<> V 
\V </> 


A * v **. 



* a 


0 r ' 0 N c 






£* L ' T '' % ( 
*>. * » I ' * 


•S> O 

Qp * 

s ^ A vS> y o * x * a> ’ <* 

t - * * A N A 1 » * , 0 M c 

0 ^ A _s^fsrs, % <*> A v V ■* A 

- <4 cA' Y|>4» «' -><v A ' M/A -f . «S 

, bo' ^ v : mmfr: "W 

’ \° ^ 3 ® ,-l '7V 

_ <* *z 2 y/jM& > ^ >> 4 ^ > vx* ^ <#. 

cA x '* v o 0 c* y ’' "■ * a c£-„ X- 

... *., 1 * i 0 .... 'bj. * 7 «»’ ^ 

” -iv A? * is ■ <?■ 

,; » w . . s . s Ar 

A- A ^ **•%. -HEPr* A ** ° 

:v 'V ,v., ^'’-'’/.^.V'-'V 4 .^. % 

A x , v2-. * <4 AAsA /%. “ r ">Sv A v j&d'/.'Vt 2 -* * 

< v >€k I . *>^ v -> 'OAs\M ^5m vT 

* V B - ( 3 ^ '■ v 



^5 ^ ^ 

> \v- V. rf. 

i ' r >» ” ^ Q * r^ A- 

^ * o m o 7 % » 

* r. ° N »y v*o, 



A c> 

j. ^ 'P. . r 

* \r> A’ ♦ 

A ,\V 






* * , ^ * 3 K 0 ‘ ^ 

^ % v x 

*• ^ A : 



-" a °^y^wj a ^ : » 

. , ^ ' J ' r *'- '/ . V ■ . , %*' ' “ * ' * /' V % 

* 'p A *r’ /t 9 > 3 ^ ^ ° Cr A ,^s><x * ' 

^ A ^ M : u y * , <4 ACv.AW wr 

'. ^ V* ^o' 

<* 

o <H ^ >- - ^ 

^ c ~2^ , / y^/ x ■/* V'iVV . v^ ^ N y ^ 




. - % /'; 

A^‘ 'Pr'. 

-t> A Ay ^ 

S S A ik J .t. J 0*\ 
A x * v 8 ^ 

AJ A ^f.O^ + 





















































Jr 
























9 


















OPINIONS OF THE PRESS. 


The Manufacturer and Builder, New York . 

An Engineer’s Handy-Book. —Mr. Roper, the writer of this work, is well 
known to many of our readers as the author of a number of useful reference 
books relating to steam-engineering, which have become deservedly popular by 
reason of their plain and intelligible style and their freedom from unnecessary 
and confusing mathematical technicalities. Mr. Roper’s object in all these hand¬ 
books has avowedly been to present facts and explain principles in language so 
plain and comprehensible that average steam-users, engineers, firemen, and 
those who are usually'found in charge of steam-machinery, can read his books 
understandingly and with profit. We would be glad to see Roper’s hand-books 
largely multiplied and distributed in every workshop, for it is only out of books 
of this kind that the average workman will be able to master the principles of 
his handiwork. The present volume is no exception to this rule; on the con¬ 
trary, we regard it to be decidedly the best of Mr. Roper’s books, both with 
regard to its substance and the manner in which the same is classified and pre¬ 
sented. 

The Locomotive, Hartford, Conn • 

Roper’s Engineer’s Handy-Book.— Published by E. Claxton & Co., of 
Philadelphia, who are the publishers of several works on steam, steam-boilers, and 
engines, from Mr. Roper’s pen. This last work is of special value to all who 
have to do with steam-boilers and engines, and it will be found a valuable shop 
companion for the mechanic. There are a great many facts collated that are 
not easily reached except through expensive books and libraries. These will be 
found of service to all classes of men, whether in trade or manufacturing. We 
commend it heartily, and believe it will have a large sale. 

National Car-Builder, New York. 

Roper’s Engineer’s Handy-Book.— This compact and comprehensive little 
volume contains a vast amount of information relative to the care and manage¬ 
ment of every class of steam-engines. It is profusely illustrated, and abounds 
in facts, figures, rules, tables, questions and answers, formuhe, etc., that are ex¬ 
ceedingly valuable to engineers, and of easy reference by means of a copious 
and well-arranged index. The various subjects are discussed with brevity and 

1 






OPINIONS OF THE PRESS. 


clearness, and with a freedom from technicality which enables the reader te 
at the pith of the matter without fishing it out f rom an ocean of words. A prom¬ 
inent feature of the book is a full explanation of the steam-engine indicator, and 
its use and advantages to engineers and others. The long experience of the 
author in this branch of engineering, and the numerous publications he has al¬ 
ready issued upon kindred subjects, give an additional value to the present 
treatise. It is printed on thin paper and in clear type, and contains 678 pages. 
Flexible tuck binding, gilt edge, suitable for the pocket. 

Forest, Forge, and Farm , I lion, New York. 

Engineer’s Handy-Book. — We have received a book with the above title, 
by the well-known author and engineer, Stephen Roper, who lias written a 
number of works on the subject of engineering. The eminent reputation of the 
author is a sufficient guarantee that the book is both interesting and useful. 
Mr. Roper has had an experience of over thirty-five years with all kinds of en¬ 
gines and boilers, and thoroughly understands locomotive, fire, marine, and 
stationary engines. This work has 678 pages, is profusely illustrated, bound in 
morocco, and contains nearly 300 main subjects, 1316 paragraphs, 876 questions 
and answers, 52 suggestions and instructions, 105 rules, formulae, and examples, 
149 tables, 195 illustrations, 31 indicator diagrams, and 167 technical terms; 
over 3000 different subjects, with the questions most likely to be asked when 
under examination, before being commissioned as an engineer in the U. S. Navy 
or revenue service; before being licensed as an engineer in the mercantile marine 
service, or receiving a certificate to take charge of a steam-engine or boiler in 
locations where such certificate is necessary. 

It is a very valuable book for engineers, and will no doubt meet with a ready 
sale. E. Claxton & Co., Philadelphia, arc the publishers. 

\ 

LeffeVs Illustrated News, Springfield, Ohio . 

Engineer’s Handy-Book : By Stephen Roper, Engineer. — The author of 
the valuable series of hand-books which we have before referred to, has just 
issued the above-named work, which must find ready way into the hands of en¬ 
gineers and steam-users throughout the entire land. It contains a full explana¬ 
tion of the steam-engine indicator, its uses and advantages, with formulae for 
estimating the power of all classes of steam-engines; also facts, figures, questions 
and tables for engineers who wish to qualify themselves for the United States 
navy, the revenue service, the merchant marine, or the better class of stationary 
engines. The work does not claim to teach how to design or proportion steam- 
engines and boilers, but rather to inform the engineer how to manage them 
intelligently. It is one of the kind of practical hand-books for which there is 
always need. The work is well bound in flexible leather, uniform with Roper’s 
other hand-books, has 678 pages, and is fully illustrated. 

o 

n 





OPINIONS OF THE PRESS. 


American Machinist, New York. 

Roper’s Engineer’s Handy-Book. — The subjects in this work have been 
treated in a brief and comprehensive way, therefore the reader is not required 
to read a number of chapters in order to acquire a little knowledge. The use 
of the indicator is treated in a plain, practical way, so that it may be readily 
understood. Abstruse formulas have been omitted and simple arithmetic used, 
thus avoiding the usual vexations among practical men, who are uneducated in 
the higher mathematics. The author has in this book given the results of his 
own practical experience, which extends over a period of thirty years and up¬ 
wards, and the work will doubtless be read with pleasure and profit by very 
many practical mechanics. 

Boston Journal of Commerce. 

Mr. Stephen Roper is well known as the author of several other handy-books 
that treat on steam, steam-boilers, and engines. This new work is, in our judg¬ 
ment, his best. Although the arrangement and classification seem a little 
peculiar, and a decided new departure in book-making, they do not detract from 
the merit of the book, which is plain, comprehensive, and instructive from the 
title-page to “ The End.” It is neatly illustrated, and creditable in the highest 
degree to both author and publishers. It will be a valuable addition to every 
engineer’s library. 

Millstone, Indianapolis, I)id. 

“The Engineer’s Handy-Book,” by Stephen Roper, Engineer, is a practi¬ 
cal treatise on the management of the steam-engine. The author says the book 
was “not written for the purpose of instructing engineers how to design or pro¬ 
portion steam-engines or boilers, but rather to inform them how to take care of 
and manage them intelligently.” The declaration is carried out in the plainest 
and most systematic manner. There is no straining after possibilities, but the 
facts, as a thorough mechanic and engineer understands them, are set forth in 
positive language and plain terms. This gives value to the work as a hand-book 
to such engineers who are not too egotistical to receive information. As a text¬ 
book for students in mechanical engineering, it will be found of great value. Its 
illustrations and tabulated matter are important features, and printed in the ex¬ 
cellent style that characterizes all the books issued from the house of E. Claxton 
& Co., Philadelphia. It is something that should be possessed by every engi¬ 
neer. 


The American Engineer, Chicago, 111. 

The Engineer’s Handy-Book.—W e are in receipt of the above work,which 
contains a description of the various forms of engines now in use, and supplies 
interesting and useful information as to the care, management, and remedy of 

q 







OPINIONS OF THE PRESS. 


defects of steam machinery and its appendages, with tables for calculating the 
power of engines. Mr. Roper in his preface says : “ This book was not written 
for the purpose of instructing engineers how to design or proportion steam-en¬ 
gines or boilers, but rather to inform them how to take care of and manage 
them intelligently, as well as to furnish to those intending to qualify themselves 
for the United States Navy, Revenue Service, Mercantile Marine, or to take 
charge of the better class of stationary steam-engines, with a plain, practical 
treatise.” It is from this standpoint, therefore, that the book ought to be judged, 
and we are sure that the large class to whom it is especially addressed will find 
it a useful appendage and book of reference in their daily work. 

The Scientific American, New York . 

A well-made pocket-book of practical information for mechanical engineers, 
particularly those of limited education, and such as may wish to qualify them¬ 
selves for service in the U. S. Navy or the mercantile marine. The more 
important engines in use are clearly described, and formulse are given for 
estimating their power. Particular attention is paid to the Steam-Engine In¬ 
dicator, its use and advantages. The author has had much experience in this 
class of work, and writes clearly and plainly. 

Engineering News, Neiv York • 

An “Engineer’s Handy-Book.” —As a writer on subjects relating to steam 
and steam engineering, Mr. Roper is now too well known to need any further 
introduction. In this, his latest contribution to steam-engineering literature, 
Mr. Roper has aimed to present to his brother engineers a “ handy-book” that 
will be to them what Trautwine’s “ Pocket-Book” is to civil engineers, and in 
doing this he has spared no labor in collecting and editing his materials. Some 
idea of the completeness of the work may be gathered from the statement of 
the publishers that it contains nearly 300 main subjects, 1316 paragraphs, 876 
questions and answers, 52 suggestions and instructions, 105 rules, formulae, and 
examples, 149 tables, 164 illustrations, 31 indicator diagrams, and 167 technical 
terms; over 3,000 different subjects, with the questions most likely to be asked 
when under examination, before being commissioned as an engineer in the U. S. 
Navy or Revenue Service; before being licensed as an engineer in the Mercantile 
Marine Service, or receiving a certificate to take charge of a steam-engine or 
boiler in locations where such certificate is necessary. The author does not 
claim to have discovered any recent special facts relating to his subject, neither 
does he claim to have written a book of instructions in designing or proportion¬ 
ing steam-engines; he aims rather to instruct how to care for and manage them 
intelligently. The book is very full and complete, and its typographical execu¬ 
tion is perfect. It must readily recommend itself as an “ ever-ready com¬ 
panion” to every steam-engineer in the country. 

4 


OPINIONS OF THE PRESS. 


j 


From the Textile Colorist, Philadelphia . 

The Engineer’s Handy-Book. —Another aid to engineering by a well 
known author, who has already done much in the way of practically educa¬ 
ting scientific students. The work before us is one of 678 pages of the most 
useful information. It treats exhaustively on the most recently invented ad¬ 
juncts to the steam-engine, and gives very full formula by which engineers can 
accurately calculate power and make reliable estimates in all branches of their 
profession. It likewise presents the most desirable instructions to young men 
wishing to stand examination for the United States Navy or Revenue Service, as 
well as the merchant marine. It is fully illustrated, and got up in a style com¬ 
mendable in the publishers and flattering to the author. 

From the American Manufacturer and Iron World , 

Pittsburg, Pa. 

Tiie Engineer’s Handy-Book : By Stephen Roper, Engineer.—Mr. Roper’s 
name is by no means unfamiliar to the readers of popular steam-engineering 
literature in this country. The book now under notice is his last, and we be¬ 
lieve the largest in bulk and the most comprehensive in scope of any work yet 
published by him. He has gathered into this single volume about all the prac¬ 
tical information relating to the care and management of a steam-engine that 
one employed as a steam-engineer would be likely to require in ordinary service. 
The leading steam-engines now in the market are illustrated in this book with 
more or less descriptive matter accompanying each, giving the reader a general 
idea of the design of the engines, the details of their construction and operation. 
The various accessories to engines and boilers receive their full share of atten¬ 
tion. The chapter relating to the indicator is well illustrated by means of nu¬ 
merous and well chosen diagrams. 

The paper, press-work, and the general make up of the book leave nothing to 
be desired. The style in which the book is written will commend itself ^those 
who want a book to read, and, thererore, free from mathematical fornriflfe, and 
we have no doubt that the class of persons whom Mr. Roper addresses will find 
in this book all they will be likely to want in connection with any (Question re¬ 
lating to the steam-engine. 


•i 


5 





OPINIONS OF EMINENT ENGINEERS, ETC. 


The following letters have been received from some 

OF THE MOST DISTINGUISHED MECHANICAL ENGINEERS, EX¬ 
PERTS, AND AUTHORS IN THE COUNTRY. 

E. Claxton & Co. Cincinnati, Ohio, Aug. 3, 1880. 

Permit me to acknowledge copy of your Roper's Engineer's Handy- 
Book. The volume contains a large amount of useful information for 
students of mechanical engineering, arranged in a condensed form, and 
cannot fail to be a valuable acquisition to young engineers and me¬ 
chanics. JOHN W. HILL. 

E. Claxton & Co. Yonkers, N. Y., Aug. 14, 1880. 

In reply to your favor of the 2d instant, I would say that I think Mr. 
Paper's “ Engineer's Handy-Book " is the best one of his recent works. 
Permit me to say that, when asked, as I often am, by the men I meet in 
charge of engines, as to what books they had best get “ to read up on the 
engine," I say “ get Poper's Works" In the future, as in the past, 
I shall take pleasure in endorsing his effort to the men for whom he has 
written. W. H. ODELL. 

Messrs. E. Claxton Co. Tr °y> N - F-» Au 9- u, 1880 . 

Your favor of a late date, as well as enclosure of “ Poper's Engi¬ 
neer's Handy-Book," duly received. Permit me to say, that I think 
the book a very valuable addition to the literature of the subjects of 
which it treats; and, while the accomplished engineer will find in this 
book many facts so plainly stated as to save much time in working up, 
the intelligent engineer and mechanic, whose opportunities in the past 
have hardly permitted his becoming fitted, and whose time in the present 
will hardly allow him to wade through the verbiage and mathematical 
demonstrations in which such knowledge as is contained in Mr. Poper's 
book is usually enveloped, will find in it a large amount of information 
stated in the common language of every-day life. Such books cannot be 
too widely distributed. The time was when their possession ivas a con¬ 
venience. The time is when their possession is almost, if not quite, a 
necessity. F. F. HEMENWAY. 

E. Claxton & Co. Passaic, N. J., Aug. 14, 1880. 

I have examined 11 Poper's Handy-Book" pretty thoroughly, and 
have no hesitancy in pronouncing the work an excellent one. It is de¬ 
cidedly out of the beaten track, and the better for it. 

WM. II. HOFFMAN. 


OPINIONS OF EMINENT ENGINEERS, ETC. 


E. Claxton & Co. Chicago, 111., Aug. 18, 1880. 

Your note of July 29th, and a copy of “ Roper's Engineer's Handy - 
Boole” were duly received. The book is well calculated to accomplish 
the purpose of the author, viz., to furnish practical and valuable infor¬ 
mation to engineers. The comprehensive description of the various 
types of automatic engines is a fund of useful knowledge, and the various 
groups of questions, the answers to which are embodied in the text, are 
very likely to cause readers to “ think,” and to fasten the ideas in their 
minds. The book is a desirable addition to an engineer's library. 

CHABLES A. HAGUE. 


E. Claxton & Co. Hamilton, Ohio, Aug. 80, 1880. 

Your esteemed favor, and also a copy of Boper's Engineer's Handy- 
Book, were duly received; and, in reply, I beg leave to say that the work 
is well got up, and I consider it of more practical value than any I have 
yet seen. It seems almost impossible to find steam literature adapted to 
the wants of steam users. This book fulfils this requirement, and de¬ 
serves a good reception at the hands of a class of men whom it may 
greatly benefit. J. W. SEE. 

E. Claxton & Co. Hartford, Conn., Sept. 8, 18S0. 

Your favor of the 29th of July came in my absence. I have just 
returned, and hasten to reply. Boper's Engineer's Handy-Book is re¬ 
plete ‘with the information that Engineers need at hand. It combines 
such portions of more pretentious works not readily accessible to the 
Engineer, as well as information from Mr. Boper's wide practical 
experience with the detailed working of Boilers and Engines, as ivill 
give it value in the Shop and Engine-room. But it has a wider range 
than this. It contains valuable tables, articles on the U. S. Naval Ser¬ 
vice, Bevenue Service, and Mercantile Service, with qualifications re¬ 
quired of persons seeking appointments in each, and numerous other 
matters that make the work a very valuable compendium. I shall keep 
a copy on my desk ready for reference, and cheerfully commend it to 
others. Business men and manufacturers will find it a very convenient 
Hand-Book. J. M. ALLEN, 

President Hartford Steam-Boiler Inspection and Insurance Company. 





OPINIONS OF EMINENT ENGINEERS, ETC. 


E. Claxton & Co. Columbus, Ohio, Oct. 25, 1880. 

I esteem this hook highly as one containing much information not 
found elsewhere in a condensed form. It hears directly on practical 
questions in mechanical engineering , especially on matters pertaining 
to the Indicator and its use. How to read a diagram and determine 
the condition of the action of engines are made clear. 

The hook is of especial value to any who may he interested in the 
peculiarities of existing engines , as I find the hook contains illustrations 
and descriptions of most of the prominent engines in use. 

S. W. BOB INS OH, 

Prof, of Mechanical Engineering, Ohio State University. 

E. Claxton & Co. Boston, Nov. 2h, 1880. 

I can give my opinion of Boper's Engineer's Handy-Book in a few 
words: it is the hook that has been needed for more than 50 years. It 
is the ortly hook on steam and the steam-engine that I know of which 
is devoid of the mysteries of algebraical formulae , and which the engi¬ 
neer or student , with only a common-school education , can read and 
understand; it consequently leaves no excuse for the ordinary engineer 
to he ignorant of the principles of steam-enqines. 

F. W. BACON , M.E. 

E. Claxton & Co. Hoboken, N. J., Dec. 51, 1880. 

Gentlemen:—I am in receipt of your favor and also a copy of Boper's 
Engineer's Handy-Book; please accept thanks for the same. I am too 
much occupied with collegerwork at the present time to give it a complete 
analysis , hut at a cursory glance I see it is full of valuable information 
for those who use or handle steam-engines , and should think it would 
have a very extensive sale. 

B. H. THUBSTON, 

Prof, of Mechanical Science, Stevens Institute of Technology . 

8 


THE 



CONTAINING 


A FULL EXPLANATION OF THE STEAM-ENGINE 
INDICATOR, AND ITS USE AND ADVANTAGES 
TO ENGINEERS AND STEAM USERS. 


WITH FORMULA 


FOR ESTIMATING THE POWER OF ALL CLASSES OF STEAM-ENGINES; 
ALSO, FACTS, FIGURES, QUESTIONS, AND TABLES FOR ENGINEERS 
WHO WISH TO QUALIFY THEMSELVES FOR THE UNITED 
STATES NAVY, THE REVENUE SERVICE, THE MER¬ 
CANTILE MARINE, OR TO TAKE CHARGE OF 
THE BETTER CLASS OF STATIONARY 
STEAM-ENGINES. 


/ 





tSVQi. 




O ji 




STEPHEN ROPER, Engineer, 


Author of 


“Roper’s Catechism of High-Pressure or Non-Condensing Steam-Engines,” 
‘‘Roper's Hand-Book of the Locomotive,” “Roper's Haud-Book of 
Land and Marine Engines,” “Roper’s Hand-Book of Modern 
Steam-Fire Engines,” “Improvements in Steam-Engines,” 

“ Use and Abuse of the Steam-Boiler,” “ Questions and 


Answers for Engineers,” etc., etc. 


SECOND EDITION, REVISED AND ENLARGED. 



PHILADELPHIA: 

E. CLAXTON & COMPANY. 
O19 . L 1881 . 

C—’ 







































I 




T7\Sl 


Copyright. 

CLAXTON, REMSEN & HAFFELFINGER. 

1880 . 












* 

£ 


INTRODUCTION. 


TT is quite customary for persons to write books on the steam-en- 
gine, and then oifer as an apology for so doing, that they have 
discovered that there is no practical treatise on the same subject in 
the market, which shows either a lack of modesty on their part, and 
a want of appreciation of what has already been written, or an un¬ 
willingness to do justice to those who have previously treated the 
same subject. There is no want of literature on the steam-engine; 
in fact, it would be difficult for the most experienced engineer or 
talented author to add anything original. The steam-engine of the 
present day is probably as perfect as it ever will be; in fact, there 
has not been any important improvement made in any class of 
steam-engines for several years, except in the quality of the mate¬ 
rials employed in their construction and refinement of workman¬ 
ship; consequently, the work of those who treat on the steam- 
engine, for the present, must be confined simply to abbreviating, 
simplifying, correcting, and explaining what has already been writ¬ 
ten, as well as noting the results of the experiments which are tried 
to test the efficiency of different designs of steam-engines. 'Who¬ 
ever will apply himself to this object in the future, will be per¬ 
forming what has long been needed. Of course, we may discover 
a new engine that will be radically different from any in use at the 
present day, which would involve the necessity of a new order of 
literature and new theories, but such an innovation is highly im¬ 
probable, and casts only a dim shadow" in the .future. 

This book was not written for the purpose of instructing engi¬ 
neers hov r to design or proportion steam-engines or boilers, but rather 
to inform them how to take care of and manage them intelligently, 








X 


INTRODUCTION. 


as well as to furnish to those intending to qualify themselves for the 
United States Navy, Revenue Service, Mercantile Marine, or to 
take charge of the better class of stationary steam-engines, with a 
plain, practical treatise. In order to enhance its value to young 
engineers, as well as those of limited education, none but the plainest 
language has been used. This has not been done for the purpose of 
encouraging the engineer to dispense with the use of mathematics, 
or discard theories, as all our great triumphs in mechanical science 
have been based on theories and demonstrated by practice. 

In the discussion of the different subjects brevity has been ad¬ 
hered to, because the spirit of the age demands it, even in the dis¬ 
cussion of the most important subjects. There can be no reason 
why the reader should be compelled to wade through chapters of 
matter to obtain information which may be condensed into a few 
terse and intelligent paragraphs, nor to deal with the dead past 
when the living present is before him. The mathematical formute 
employed have been abbreviated, since it is immaterial how a prob¬ 
lem is worked, providing the result is correct and susceptible of 
easy explanation. Up to the present time, the knowledge to intelli¬ 
gently apply the steam-engine indicator has been confined to a few 
persons in every country styling themselves experts. This partly 
arose from the fact that authors who have heretofore treated on 
this subject were men of literary ability and well versed in mathe¬ 
matics, who found it more agreeable to elucidate their subject in 
their own peculiar style than in any other. 

The writer’s experience of over thirty-five years, and his asso¬ 
ciation with all classes of engineers, enable him to understand fully 
the kind of information most needed by the average engineer. Con¬ 
sequently, he has undertaken the task of furnishing it, and how well 
he has succeeded in the accomplishment of his object, he cheerfully 
leaves to the reader to decide. If it should appear that he has suc¬ 
ceeded in imparting useful and important information to the mem¬ 
bers of a profession to which he himself belongs, he will feel amply 
rewarded for his efforts. S. R. 




CONTENTS 


O t 1 




For a full reference to the Contents in detail, see Index, p. 673. 


PART FIRST. 

PAGE 

The Centennial Corliss Engines.25 

Steam Engineering.27 

Facts that should be Borne in Mind by Engineers" . . 34 

Wright’s Automatic Cut-Off Engine.38 

Examination of Candidates.40 

Necessary Qualifications of Candidates Applying for Ap¬ 
pointments as Cadet Engineers in the U. S. Navy . . 40 

Examination in Grammar.42 

Spelling.43 

Examination in Arithmetic.43 

Examination in Geography.47 

Examination in Natural Philosophy.49 

Woodbury, Booth & Pryor Automatic Cut-Off Engine . . 52 

Qualifications of Candidates for the U. S. Revenue Service 57 

Standard of Examination for Assistant Engineer in the U. S. 

Revenue-Cutter Service.58 

First Assistant Engineer.58 

Examinations for the Mercantile Marine Service . . 59 

Qualifications of Stationary Engineers.60 

Locomotive Engineers.62 

Steam. 63 

Table showing the Increase of Sensible and the Decrease of Latent 

Heat in Steam, according to Pressure.65 

Table showing the Effluent Velocity with which Steam, at different 
Pressures, will Flow into the Atmosphere, or into Steam at a lower 

Pressure.67 

xi 















X1L 


CONTENTS. 


PAGE 

Rule for Finding the Amount of Gain derived from Work¬ 
ing Steam Expansively .67 

Table of Hyperbolic Logarithms to be used in Connection with the 

above Rule.68 

Table of Multipliers by which to find the Mean Pressure of Steam at 

Various Points of Cut-Off ..69 

Table of Constant Numbers by which to Ascertain the Average Press¬ 
ure of the Steam against the Piston for different Pressures and Points 
of Cut-Off, from ^ to | of the Stroke ...... 69 

Table of Constant Numbers for Finding the required “Lap” for Slide- 
Valves when the Travel of the Valve is known . . . .70 

Table showing the Average Pressure of Steam upon the Piston through¬ 
out the Stroke, when Cut-Off in the Cylinder is from £ to com¬ 
mencing with 10 Pounds and advancing in 5 Pounds up to 55 

Pounds Pressure. 71 

Table showing the Average Pressure of Steam upon the Piston 
throughout the Stroke, when Cut-Off in the Cylinder is from J to 
commencing with 60 Pounds and advancing in 5 Pounds up to 105 

Pounds Pressure . . . ..72 

Table showing the Average Pressure of Steam upon the Piston 
throughout the Stroke, when Cut-Off in the Cylinder is from ^ to 
commencing with 110 Pounds and advancing in 5 Pounds up to 

150 Pounds Pressure. 73 

Table showing the Temperature of Steam at different Pressures, from 
1 Pound per Square Inch to 220 Pounds, and the Quantity of Steam 
produced from a Cubic Inch of Water, according to Pressure . . 74 

Explanation of Table .76 

Table of Elastic Force, Temperature, and Volume of Steam from a 
Temperature of 32° to 457° Fah., and from a Pressure of 0*2 to 900 

Inches of Mercury.76 

Table showing the Temperature and Weight of Steam at different Press¬ 
ures from 1 Pound per Square Inch to 300 Pounds, and the Quantity 
of Steam produced from 1 Cubic Foot of Water, according to Pressure 81 
Table showing the Steam Pressure in Pounds per Gauge; the Abso¬ 
lute Pressure in Pounds and Inches of Mercury ; the Temperature ; 
the Total Heat in Steam per Pound; the Latent Heat per Pound; 
the Heat of the Water; the Relative Volume and Weight of Steam 


per Cubic Foot for various Pressures.85 

The Brown Automatic Cut-Off Steam-Engine . . . .88 

The Harris Corliss Steam-Engine.95 

Questions for Engineers.99 
















CONTENTS 


• • • 
Xlll 

PART SECOND. 

PAGE 

Steam-Engines in General.102 

Compound Engines.. 

Simple Engines.. 

Table of the Average Performances of different Designs of Pumping- 

Engines .. 

Uncertainty of Tests for the Purpose of Comparing the 

Relative Economy of Marine Engines'.11G 

The Locomotive.119 

The Steam Fire-Engine.120 

The Woodruff and Beach Automatic Cut-Off High-Pressure 

Engine. 124 

Automatic Cut-Off and Throttling Engines . . . 130 

Throttling Engines.131 

Steam-Engine Cut-Offs.132 

Design of Steam-Engines.134 

Duplicating the Parts of Steam-Engines.130 

Fitting the Cranks of Steam-Engines to their Shafts . 137 
The Putnam Machine Company’s Automatic Cut-Off Engine 138 

How to Put an Engine in Line.141 

How to Set up a Stationary Engine.143 

How to Reverse an Engine.145 

How to Repair Steam-Engines.140 

How to Increase the Power of the Steam-Engine . . .148 

The Greene Automatic Cut-Off High-Pressure Engine . .150 

The Dead-Centre.152 

The Causes of Knocking in Steam-Engines .... 153 

The Remedies for Knocking in Steam-Engines .... 155 

The Douglas Automatic Cut-Off Engine.159 

Technical Terms Applied to Different Parts of Steam-Engines 100 

Terms Formerly Applied to Different Parts of Steam-En¬ 
gines, BUT WHICH HAVE BECOME OBSOLETE .... 101 

Questions.102 

PART THIRD. 

Bed-Plates and Housings.103 

Steam-Cylinders.104 

Table showing the Proper Thickness for Steam-Cylinders from 0 to 90 

Inches.100 

2 















XIV CONTENTS. 

PAGE | 

Steam-Pistons .167 i 

Piston-Rods.169 

Table of JJnits of Horse-Power for different Piston Speeds . . 170 

Table showing Length of Stroke and Number of Revolutions for dif¬ 
ferent Piston Speeds in Feet per Minute . . . . .172 

Piston, Connecting-Rod, and Crank Connections . . .175 

The Reynolds Corliss Engine . ..177 

Steam- and Exhaust-Pipes.180 

Rock-Shafts ..181 

Cross-Head Bearings. ..181 

Valve-Rods ..182 

The Eccentric.182 

The Crank . 183 

Crank-P i ns ..185 

Crank-Shaft Journals and Main-Bearings . . . 187 

Keys, Gibs, and Straps.188 

The Link . . . . 189 

Fly-Wheels.192 

The Watertown Automatic Cut-Off Engine . . . .194 

Steam-Engine Governors.197 

How to Balance the Reciprocating and Revolving Parts 

of Vertical Engines. . 202 

Heating in Journals and Reciprocating Parts of Steam- 

Engines . ... 202 

IIeversing-Gear for Marine Engines ....’. 203 

The Slide-Valve.205 

The Wiieelock Automatic Cut-Off Engine .... 214 
How to Determine the Amount of Lap and Lead on a Valve 
without Opening the Steam-Chest, and whether it is 

Equal at both Ends or not.218 ' 

Table showing the Amount of “ La}>” required for Slide-Valves when 

the Steam is to be Worked expansively.220 

Friction of Slide-Valves.221 

How to Set the Valves of Steam-Engines.224 

Valves and Valve-Gear.226 

Valves and Cocks connected with Engines and Boilers . 229 

’ Pipes.231 

The Wells Two-Ptston Balance-Engine.232 

Instructions for the Care of Steam-Engines .... 235 
Piston-Rod and Valve-Rod Packing, and How to L t se it . 237 
Ward well’s High-Pressure Valveless Engine .... 240 




















CONTENTS 


XV 


PAGE 


Lubricants.243 

Questions.246 


PART FOURTH. 


The Steam-Engine Indicator : Its Invention and Improvement 251 

Tabor’s Indicator.. 259 

Functions of the Indicator.261 

Technical Terms Used in Connection with the Employment 

of the Indicator.263 

How to Attach the Indicator.268 

Motion of the Paper Drum.269 

The Most Accurate Methods of Testing the Adjustments . 274 

• • • • * 

Diagrams taken from Automatic Cut-Off Engines . . . 278 

Application of the Theoretic Curve.280 

• 9 ■» 

The Initial Pressure, or Steam-Line.282 

• o 7 

The Mean Effective Pressure.283 

To Space the Ordinates.285 

■- 

To Calculate the Indicated Horse-Power.285 

Theoretical Economy.286 

How to Calculate Theoretical Kate of Water Consumption 288 

« • * 

Indicator Diagrams. 291-320 

— • • 

Formula for Finding the Theoretical Clearance when the Seale is 

known ..316 

Formulae for Finding the Horse-Power of Steam-Engines by Indi- 

0 * r 

cator Diagrams ..318 

Another Formula..319 

What Indicator Diagrams Show, and How they Show it . 321 

* * 

The Planimeter . 

Steam-Engine Economy 


Location of Steam-Engines 
The Porter-Allen High-Speed Engine 
Questions .... 


323 

325 

329 

330 
334 


PART FIFTH. 

Condensers 338 

Table showing the Force with which Uncondensed Steam arising from 
Water in Condenser resists Ascent or Descent of Piston, according 

to its Temperature . 341 

Relative Quantity of Injection-Water required to Condense 
a Certain Yolume of Steam .342 

















XVI 


CONTENTS 


PAG! 

The Injector Condenser . 345 j 

Independent Condenser and Air-Pump . 346 t 

The Vacuum . 348 i 

Table showing Vacuum in Inches of Mercury and Pounds Pressure 

per Square Inch. 349 < 

Air-Pumps.353 

The Saeinometer .. 360 j 

Table showing Proportion of Salt in Water of different Seas . . 362 

Table showing Boiling-Point of Salt Water at different Degrees of 
Density, when the Barometer stands at 30 Inches .... 362 

The Barometer.364 

Table showing Weight of Atmosphere per Square Inch corresponding 

with different Heights of Barometer.365 

Thermometers.365 

Marine Steam-Engine Register.367 

Spring-, Mercury-, Syphon-, and Vacuum-Gauges . . . 369 

The Mariner’s Compass. 373 I 

Table of Rhumbs, or Points of the Compass.374 

Table showing Magnitudes and Velocities of the Planets . . .375 

Technical Terms and Definitions Used in Navigation . . 376 

Table of Miles as Measured by Various Nations .... 382 

Length of Days in Different Countries.382 

Table of Sailing Distances from New York to different Parts of the 

World, in Geographical Miles.383 

Table of Latitude and Longitude of Places.384 

Table showing Time at different Places when it is 12 o’clock Noon at 

New York.385 

Table of Miles and Knots, Knots and Miles . . » . . 386 

Marine Signals.386 

Marine Whistle-Signals.389 

Marine Bell-Signals.390 

Light Signals for Ocean Steamships.390 

Railroad Signals.391 

Train Signals.392 

Enginemen’s Signals.393 

Conductors’ Signals.394 

Signals by Lamp.394 

The Screw-Propeller ......... 394 ! 

The Paddle-Wheel.396 

Pumps. 400 I 

Injectors. 406 | 





















CONTENTS. 


XVII 


William Sellers & Co.’s Injector. 

Table showing Steam-Pressure required to Lift and Deliver Water 
with Sellers’ Fixed-Nozzle Lifting Injector . 

Sellers’ Non-Adjusting Fixed-Nozzle Injector, with Lifting 

Attachment, for Stationary Boilers. 

Table showing Maximum and Minimum Delivery of Sellers’ Self- 
Adjusting, 1876) Injector No. 6 ; Temperature of Delivered Water; 
Pressure against which Injector delivers Water, and Highest Tem¬ 
perature of Feed admissible; Water flowing to Injector under 15 
Inches Head ; Waste-Valves Shut .- 
Table of Capacities of Sellers’ Injectors 
Temperature of Feed-Water .... 

Rue’s “Little Giant” Injector 

Table of Capacities of Rue’s “ Little Giant” Injector 

Friedman’s Injector. 

Table of Capacities of Friedman’s Injectors 

The Keystone Injector. 

The Keystone Lifting Injector . 

The Eclipse Injector. 

The Clipper Injector. 

Table of Capacities of Clipper Injectors 

The Inspirator. 

Table of Capacities of the Hancock Inspirator . 

Instructions for Setting up, Properly Attaching 
justing Injectors. . . • . 

The Ejector or Lifter. 

Jamison’s Steam Water-Ejector 

Table of Capacities of Jamison’s Steam Water-Ejector 

Questions. 


PAGE 

408 

412 

412 


AND 


Id- 


416 

417 

417 

418 
420 
420 
422 

422 

423 

424 
426 
428 
430 
432 

432 

434 

435 

435 

436 


PART SIXTH. 

Steam-Boilers.442 

Bursting Pressure of Cylindrical Steam-Boilers . . . 448 

Rules. 451, 452, 468 

Boiler-Stays ..453 

Stay-Bolts.454 

Table showing the Breaking S'train of Iron and Copper Stay-Bolts . 455 

Scale in Steam-Boilers.455 

Foaming in Marine-Boilers.457 

Priming. 458 

2 * B 













XV111 


CONTENTS 


PAGE 

Corrosion, and its Analogy to Combustion.460 

Manual and Mechanical Firing.461 

Technical Terms applied to Firing.462 

Technical Terms employed in Relation to Boilers. . . 462 

Friction of Riveted Seams.463 

Calking.* 463 

Steam-Boiler Explosions.464 

Safety-Valves.465 

Draught in Chimneys.469 

Smoke.473 

Feed-Water Heaters.474 


Table showing Units of Heat required to Convert One Pound of 
Water, at the Temperature of 32°, into Steam at different Pressures 475 
Technical Terms applied to Adjuncts of the Steam-Boiler 476 
Instructions for the Care and Management of Steam-Boilers 478 

Boiler Materials ..480 

Definitions of the Technical Terms applied to the Differ¬ 
ent Kinds of Boiler-Plate.486 

Questions.491 


PART SEVENTH. 

Air .496 

Table of Altitudes above Sea-Level, and the corresponding Atmos¬ 
pheric Pressures, deduced from the Observations of the Hayden 

Expedition to the Rocky Mountains.. 498 

Table showing the Force of the Wind in Pounds per Square Foot at 

different Velocities.499 

Horse-Power of Wind-Storms .499 

Altitude of the Highest Mountains in the World . . 500 

Highest Waterfalls in the World. 500 

Table showing Relative Volumes of Air at various Temperatures . 501 

Technical Terms which are applied to Fluids and Vapors, 
and which Bear a Certain Relation to the Steam-Engine 502 

Fuel.503 

Heat.507 

Table showing the Latent Heat of various Substances . . . 508 

Table showing the Radiating Properties of different Substances. . 508 

Table showing the Effects of Heat upon different Bodies . . . 508 

Table showing the Specific Heat of different Substances . . . 509 

Table showing the Relative Weight and Volume of different Gases . 509 




















CONTENTS. 


XIX 


PAGE 


Table showing the Non-conducting Properties of different Materials 

at Even Thickness.510 

Combustion .510 

Table showing the Total Heat of Combustion of various Fuels . .512 

Water .514 

Table showing the Quantity and Weight of Water in Pipes One 
Fathom in Length (6 Feet), and of different Diameters from 1 to * 

12 Inches.518 

Table showing the Quantity of Water per Lineal Foot in Pumps or 

Vertical Pipes of different Diameters . *.519 

Table showing the Weight of Water at different Temperatures . . 520 

Table showing the Boiling-Point f6r Fresh Water at different Alti¬ 
tudes -above Sea-Level.520 

Table showing the Capacity of Cisterns and Tanks, Computed in Bar¬ 
rels of 31J Gallons . 521 

Table showing the Power required to raise Water to different Alti¬ 
tudes, varying from 1 Foot to 20,000 Feet.522 

Table showing the Capacity of Cisterns in Gallons for each 10 Inches 

in Depth ... . 523 

Table showing the Daily average Number of Gallons of Water per 
Individual in different Cities, including the Quantity Used for 
Manufacturing Purposes, Fountains, etc. . .... 524 

Vapors .525 

Table showing the Temperature of Saturated Vapor in Atmospheres, 

according to Zeuner ..525 

Table showing the Pressure and Temperature of the Vapors of Water 

from 32° to 400° Fall.526 

Gases .530 

Technical and Chemical Terms as applied to Substances that 
Bear Relations to the Steam-Engine both in Theory and 
Practice .534 


Areas of Circles. 

Rules. 

Significations of Signs Used in Calculations . 

The Cipher ......... 

Table of Diameters and Areas of Small Circles . 

Table containing the Diameters, Circumferences, and Areas of Circles 
from yV of an Inch to 100 Inches, advancing by of aii Inch up 
to 10 Inches, and by £ of an Inch from 10 to 100 Inches . . 544 

Table of Logarithms of Numbers from 0 to 1000 .... 555 

Table of Hyperbolic Logarithms ....... 557 


536 

538 

542 

542 

543 
















XX 


CONTENTS. 


Peculiarities of Multiplication. 

Decimal Arithmetic. 

Table of Vulgar and Decimal Fractions of an Inch . 

Table of Common and Decimal Fractions .... 

Units. 

Table showing all the Units of Length Recognized in England 

the 16th Century. 

Atoms and Molecules. 


FAGE 

. 560 
. 560 
. 561 
. 561 
. 562 
since 

. 565 
. 566 


Table of Squares, Cubes, and Square and Cube Roots of all Numbers 
from 1 to 620 ........... 567 

The Wetherill Corliss Engine.583 

Emergencies.584 

Questions.585 


PART EIGHTH. 

Lexicon of Definitions of Central, Mechanical, and Dynam 


ical Forces. 587 

Metals and Alloys. 612 

Table of Mineral Substances and their Chemical Equivalents . .612 


Table showing the Heat-Conducting Properties of Different Metals . 614 
Table showing the Tenacity or Tensile Strength of Different Metals . 614 
Table showing the Proportion of Carbon in the various Grades of 


Iron and Steel.* • 615 

Alloys and Compositions .616 

Solder .617 


Table showing the Average Crushing Load of different Materials, or 
the Weight under which they will Crumble ..... 617 
Table showing the Tensile Strength, or the Strain that will Pull dif¬ 
ferent Metals Asunder on a Straight Pull . . . . .618 

Table showing the Tensile Strength of different Kinds of Wood . 618 
Table showing the Weight of Castings by Weight of the Patterns . 620 
Table showing the Shrinkage of Castings of different Metals . . 620 

Table showing the Weight and Bulk of different Substances in Cubic 

Feet, Pounds, and Tons.620 

Table showing the Weight of different Metals per Cubic Foot . . 621 

Table showing the Actual Extension of Wrought-Iron at various 

Temperatures.. . . . 021 

Table showing the Linear Dilatation of Solids by Heat . . . 622 

Table deduced from Experiments on Iron Plates for Steam-Boilers, 
by the Franklin Institute, Philada.623 










CONTEXTS. 


XXI 




PAGE 

Table showing the Strength of Copper Boiler-Plates at different Tem¬ 
peratures, deduced from Experiments by the Franklin Institute of 
Phila. The Standard Strength at 32° being 32,800 Pounds per 

Square Inch.623 

Table showing the Weight of Cast-Iron Balls from 3 to 13 Inches in 

Diameter.. . .624 

Table showing the Weight of Cast-Iron Plates per Superficial Foot 

as per Thickness.624 

Table showing the Weight of Bound Iron from £ an Inch to G Inches 

in Diameter, 1 Foot Long.625 

Table showing the Weight of Boiler-Plates 1 Foot Square and from 

t X 6 of an Inch to an Inch Thick.62G 

Table showing the Weight of Square Bar-Iron, from \ an Inch to G 

Inches Square, 1 Foot Long.62G 

Table showing the Weight of Cast-Iron Pipes, 1 Foot in Length, from 
i Inch to 1] Inches Thick and from 3 Inches to 24 Inches Diameter 627 
Tables showing the Standard Weights of Cast-Iron Water- and Gas- 

Pipes .628 

Table showing the Tensile Strength of various Qualities of American 

and English Cast-Iron .... G28 

Table showing the Tensile Strength of various Qualities of American 

Wrought-Iron.629 

Table showing the Kesults of Experiments made on different Brands 
of Boiler-Iron at the Stevens Institute of Technology, Hoboken, N. J. 630 
Table giving the Proportions of the United States or Sellers’ Stand¬ 


ard Threads for Screws, Nuts, and Bolts.631 

Speed, Power, Capacity, and Dress of Millstones . . . G32 

Speed of Circular Saws. G32 

Table of Coefficients of Friction between Plane Surfaces . . . 633 

Non-Conducting Covering for Steam-Boilers and Pipes. . 634 

Belting.637 

Gearing. 645 

Fitchburg Steam-Engine Company’s Automatic Cut-Off Engine 648 

The Improved Circulating Salinometer.650 

Crosby’s Adjustable “Pop” Safety-Valve. 654 

The Improved Planimeter. 656 


Crosby’s Improved Steam-Pressure Hydraulic, Combination, 


Vacuum, and Self-Testing Gauges.* . 657 

The Atlas Corliss Engine. 663 

Questions.668 

Index. 673 









LIST OF ILLUSTRATIONS. 

PAGE 

The Centennial Corliss Engine,.24 

Wright’s Automatic Cut-Off Engine.3G 

Woodbury, Booth & Pryor’s Automatic Cut-Off Engine, . 53 

Double-Slide Valves,.55 

Semi-Botary Valves,.55 

The Brown Automatic Cut-Off Engine,.89 

Harris Corliss Engine,.93 

Modern Marine Compound Engine,.110 

Section of Marine Compound Engine, .Ill 

The Woodruff & Beach Automatic Cut-Off High-Pressure 

Engine,.125 

The Putnam Machine Company’s Automatic Cut-Off Engine, 139 

The Greene Automatic Cut-Off High-Pressure Engine, . 150 

The Babbitt & Harris Steam-Piston,.167 

Piston, Connecting-Bod, and Crank Connection, .... 175 

The Beynolds Corliss Engine . . . . '. . .178 

The Crank,.1S3 

The Link,.184 

Valve-Gear,.199 

The Watertown Automatic Cut-Off Engine, . . . .195 

The Waters Governor,. 197 

The Shive Governor,. .199 

Beversing-Gear,.203 

Diagrams of Slide-Valve,. 204-213 

The Wheelock Automatic Cut-Off Engine, . . . .215 

Poppet-Valves,.223 

Slide-Valves,.230 

The Wells Two-Piston Balance-Engine,.233 

The Wardwell Valveless Engine, ...... 241 

The Steam-Engine Indicator,.251 

Thompson’s Indicator,.251 

Crosby’s Improved Indicator,.255 

Section of Crosby’s Indicator,.257 

Tabor’s Indicator,.260 

Section of Tabor’s Indicator,.261 

Bichards’ Parallel Motion Indicator,.275 

Indicator Diagrams,. 291-320 

The Planimeter, . . •. 323, 656 

Diagram Measured by the Planimeter,.325 


XXII 

















LIST OF ILLUSTRATIONS. 


XX111 


The Porter-Allen High-Speed Engine, 

Surface Condenser . 

The Injector Condenser, .... 

Independent Condenser and Air-Pump, 

Independent Air- and Circulating-Pump, 

Section of a Marine Air-Pump, 

Independent Marine Circulating-Pump, 

Marine Wrecking-Pump, . 

The Salinometer, 

The Hotwell Thermometer, . 

The Uptake Thermometer, 

Marine Steam-Engine Register, 

Spring Steam-Gauges, 

Marine Whistle-Signals, . 

Pumps,. 

William Sellers & Co.’s Injectors, 

Rue’s “Little Giant” Injector, 

Friedman’s Injector, . 

The Keystone Injector, . 

The Eclipse Injector, 

The Clipper Injector, 

Mack’s Fixed-Nozzle Injector, 

The Inspirator, .... 

The Ejector or Lifter, . 

Jamison’s Steam Water-Ejector, 

Water-Tubular Marine-Boiler, 

Fire-Tubular Marine-Boiler, . 

Direct Flue and Return Tubular Marine-Boiler, 
Methods of Bracing Marine Steam-Boilers, 

The Buckeye Automatic High-Pressure Cut-Off Engine 
Diagrams of Circles, 

The Wetiierill Corliss Engine, 

Steam- Joints, .... 

Back View of the Fttchburg Automatic Cut-0 
The Fitchburg Governor, 

Circulating Salinometer, 

Crosby’s Adjustable “Pop” Safety-Valve 
Exterior View of Crosby’s Steam Gauge, 

Interior View of the Original Bourdon Steam 
Interior View of Crosby’s Steam Gauge, 

Crosby’s Self-Testing Steam Gauge, 

Crosby’s Vacuum Gauge, .... 

The Atlas Corliss Engine, 


f Engine, 


Gauge, 


PAGE 

. 331 

. 338 
. 344 
. 348 
. 352 
. 353 
. 358 
. 359 
. 360 
. 366 
. 366 
. 367 
369-371 
. 389 
. 401 
. 409 
418, 419 
. 421 
. 422 
. 425 
. 426 
. 429 
430, 431 
. 434 
. 435 
. 442 
. 443 
. 446 
. 450 
. 489 
537, 538 
. 582 
. 634 
. 647 
. 649 
. 651 
. 654 
. 658 
. 658 
. 659 
. 660 
. 660 
. 661 















24 


Centennial Corliss Engine 












































































































































THE 

ENGINEER'S 

HANDY-BOOK. 

PART FIRST. 

The Centennial Corliss Engines. 

The Centennial Corliss Engines were beam-engines of the Cor¬ 
liss type, with all the latest improvements, and nominally of 700 
horse-power each, or 1400 horse-power together. The cylinders 
were 40 inches in diameter, with 10 feet stroke. They were pro¬ 
vided with air-pumps and condensers, consequently they could be 
worked either condensing or non-condensing, and were intended 
to work with from 25 to 80 lbs. of steam pressure, according to 
the requirements of the exhibition. The gear fly-wheel was 30 
feet in diameter, 2 foot face, and weighed 56 tons; it was un¬ 
doubtedly the largest gear-wheel ever made. The pinion that 
was driven by this large fly-wheel was a solid casting 10 feet in 
diameter, weighing 17,000 lbs., and was the largest ever made. 
The main frame was A shaped, having the journals for the beam- 
centres on the top, and the legs bolted to the bottom of the cylin¬ 
der on one side, and to the main crank-shaft journals on the 
other. 


3 


25 




26 


THE ENGINEER’S II ANDY -BOOK. 

The walking-beams were of the web-beam pattern, and made 
of cast-iron, and, in consequence of their peculiar shape, detracted 
very much from the general appearance of the engine. They 
were 9 feet wide at the centre, and 27 feet long, each weighing 
22,000 lbs. The cross-head guides extended from the upper cylin¬ 
der-heads to the top gallery, and were provided with screws by 
which they, as well as the cylinder-heads, might be lifted to admit 
of access to the pistons. The piston-rods, which were made of 
steel, were 6f inches in diameter. The cranks were highly fin¬ 
ished, and weighed 10,000 lbs. each. The connecting-rods were 
24 feet long. The steam-valves received their motion from a 
wrist-plate and a system of levers similar to those employed in 
the ordinary Corliss engine, and the releasing gear for them was 
entirely original, and very ingenious, though the exhaust-valves 
ended their vibrations by an abrupt kick or jerk. 

The height of the engines, from the floor to the top of the walk¬ 
ing-beams, was 39 feet, and their weight, with all their adjuncts 
and attachments, was over 700 tons. The engines were supplied 
with steam by 20 upright Corliss boilers, of 70 horse-power each. 
The main steam-pipe was 18 inches in diameter and 320 feet long. 
The engines rested on a platform 55 feet in diameter, and 3| feet 
above the floor of the building. The top of the frame was sur¬ 
rounded by a circular gallery, which afforded access to the beams 
and all the upper works ; this gallery was reached by a semi-cir¬ 
cular stairway on each side. These engines were objects of general 
interest and curiosity, and served to illustrate the wonderful de¬ 
velopment of the steam-engine in this country, and the amount 
of inventive genius that must have been devoted to its improve¬ 
ment. 

After the close of the Centennial thev were taken down and 

V 

removed to the builder’s establishment, Providence, R. I., where 
they remained until recently, when they were sold to the Pull¬ 
man Palace Car Co. for the purpose of furnishing the motive- 
power for their works, near Chicago, and also the power for the 
Allen Paper Car-Wheel Works adjoining. 


THE ENGINEER’S HANDY-BOOK. 


27 


Steam Engineering. 

Steam Engineering has assumed such vast proportions as 
an agent of modern progress and civilization, that it has given 
birth to a profession whose scope and functions are not yet very 
clearly defined. The engineer’s duty, in the performance of his 
daily routine, involves the application of the laws of Nature in 
various ways, to understand and explain which require a wide 
range of scientific knowledge. While there are to be found in 
the profession men whose intelligence and acquirements would 
shed lustre on any calling, there are others who, by their loose dis¬ 
regard of correct rules, show that they are laggard in the acquisi¬ 
tion of that real knowledge so essential to men in their profession. 
This is to be regretted, in view of the vast amount of property 
and the great number of valuable lives intrusted to their care, 
both on sea and land. But whenever any attempt is made to induce 
engineers to qualify themselves for their calling, the effort is met 
with the old stereotyped question regarding the relative merits of 
theoretical and practical engineers, or the comparative value of 
theory and practice. The practical men, who have no theoretical 
knowledge, scoff at the theorists, and the latter sneer at the former. 
It requires very little experience on the one hand, and not much 
study on the other, to show that each are equally important, only 
in different ways. Both parties should know that “ Theory and 
Practice make perfect.” Theory, together with practical experi¬ 
ence, will, without doubt, enable men to excel in whatever work 
they may undertake. Therefore, it should be the highest ambition 
of engineers to combine theory with practice, and prove the one 
by the other. 

This object may be effected by devoting a portion of their 
leisure hours to study, and by pursuing a systematic course of 
self-culture. The engineer whose early training has been neglected, 
and who is now debarred from the advantages of a good educa¬ 
tion, need have no cause for despondency, because the extra exer¬ 
tion and effort required to educate himself will confer advantages 





28 the engineer’s handy-book. 

of their own, which the routine work of a school cannot develop. 
Of course, there are men in this, as in all other callings, who will 
fail, however much they may try to accomplish in the way of 
educating themselves. This arises from the fact that, though 
morally all men may be equal, intellectually they never can be 
so. Consequently, the ability of men to educate themselves varies 
in proportion to the amount of natural intelligence they possess. 
But in any case, study gives quickness of apprehension, enables a 
man to profit by all the recorded experience of others, develops 
a power of appreciation and concentration, enforces exactness and 
accuracy, and, if properly directed, teaches men to classify facts, 
make proper deductions and reason logically. The knowledge 
acquired from the study of books is of inestimable value to the 
young engineer, as without it he can never be thoroughly qualified 
for the duties of his profession, since he will be lacking in certain 
definite information which can only be obtained from them, owing 
to the want of which he is almost sure to be not only narrow¬ 
minded, but also very slow to receive new ideas or to estimate the 
proper value of old ones. 

Such persons, if occupying positions in which they exercise 
authority, are very apt to become intolerant of other people’s 
opinions, to assume that all knowledge begins and ends with them¬ 
selves, or with what they have learned, and to over-estimate their 
own ability. They are apt to be self-conceited, a quality which 
too many in every calling possess, mistaking it for an independent 
spirit. One of the commonest excuses for ignorance is the stereo¬ 
typed expression, “ I am too old to learn.” This, if made in sin¬ 
cerity, is a great mistake, as it is a false pride which neglects an 
opportunity to learn because it comes late in life, and it is a false 
fear which shrinks from an effort on account of its difficulty. One 
fact very important to be considered in this connection, is, that 
knowledge throws light upon itself; and that it is the first step 
only that must be taken gropingly, as it were in the dark, as the 
bugbears in such cases, like shadows, vanish the moment they are 
boldly approached, and will be found to be mere shadows after 


THE ENGINEER^ HANDY-BOOK. 


29 


all. Truths are in the main simple and easy to be understood, 
and are daily being brought more within the grasp of the most 
ordinary comprehension by means of good books, which may be 
had at trifling cost. It is frequently asserted, by members of this 
calling, that they are no book-engineers ; which statement betrays 
their ignorance of the manner in which some of the most valuable 
books on the steam-engine originated. They were written by en¬ 
gineers of experience, who wished to advance their profession, and 
who thought that, if their predecessors could commence their 
studies in their young days, they themselves might advance and 
improve still further, leaving the benefit of their experience to 
posterity ; the art would therefore advance with the age. As much 
information may be learned in a few weeks from the works which 
they have left us, as had taken them years of observation and trial 
to ascertain. 

Most of the abuses connected with steam engineering have 
arisen from two causes, viz., avarice and ignorance; avarice on 
the part of owners of steam-engines and steam-boilers, who enter¬ 
tain the idea that cheap steam-engines and boilers might be 
managed by a class of persons who were willing to work for very 
low wages; and ignorance on the part of those who claimed to be 
engineers, but who were only men of all work, or at best mere 
laborers in the treadmill of routine (stoppers and starters). It is 
evidently one of the greatest mistakes connected with the use of 
machinery, to intrust its care and management to persons of in¬ 
ferior judgment, as a competent engineer, who could command 
good wages, would probably save three times the difference by his 
judgment and skill in its proper maintenance. If engineers wish 
to raise the standard of their profession to what it ought to be, 
and command remunerative compensation for their services, they 
may do so by educating themselves, and not otherwise. It will 
not do for them to shrug their shoulders, and claim to be “ prac¬ 
tical men,” who reject theories, because it is well known that such 
men have become a nuisance in every branch of mechanics, being 
the least progressive, the least enlightened, and the most stubborn 
3* 


30 


THE ENGINEER’S HANDY-BOOK. 


in the assertion of their views; because their minds are cramped, 
and will not allow of either the substitution or the admission of 
ideas different from their own, however crude and primitive they 
may be. 

The engineer of the ferry-boat Westfield belonged to this class. 
Although he had been fourteen years an engineer on tug- and 
ferry-boats, he was unable to tell the figures on the steam-gauge; 
and, at the investigation that followed the frightful disaster that 
occurred on board that ill-fated boat, on being asked what a va¬ 
cuum was, answered that “ he thought it was foul air.” It was also 
in evidence that the chief engineer of the line on which he was 
employed was equally wanting in that practical knowledge that 
ought to be possessed by a person occupying his position. These 
may, perhaps, be said to be extreme cases, but they will only 
prove to be so when it can be shown that there are not hundreds 
of others occupying the same positions who are not much better 
informed. No man is practical unless he proves practice by 
theory and theory by practice, and who attaches any importance 
to statements not sustained by facts. Such men can always be 
distinguished from the self-styled “ practical men,” by an unassum¬ 
ing manner, and by rarely making any pretensions; when ex¬ 
pressing their opinions, they have a tendency to underrate their 
own ability, not because they pretend to be less capable than they 
really are, but (as so many men have become pretentious in their 
manners and expressions) because they fear they may be con¬ 
sidered as belonging to that class. On the other hand, the self- 
styled variety are continually thrusting themselves forward, and 
can easily be distinguished by the profuse use of the pronoun “I,” 
which is evidence of conceit or ignorance, or perhaps of both. 

A great deal has been said and written on the subject of licens¬ 
ing engineers, but there seems still to be as great a diversity of 
opinion, as to the benefit to be derived from it, as on any other 
connected with the profession. Many engineers are of the opinion 
that, in consequence of the loose and uncertain way in which 
examinations for licenses are now conducted, a law that would 


THE ENGINEER’S HANDY-BOOK. 


31 


require every engineer to submit to a rigid examination, would 
prevent all but first-class men from being employed as engineers. 
But while all agree that there should be a license law to reach all 
classes of engineers, there are more formidable difficulties to be 
overcome in the impartial execution of such a law than appear 
at first sight. In the first place, it would be almost impossible to 
place the office of examiner or inspector beyond the reach of 
political influence, consequently his decisions would, in many in¬ 
stances, be likely to be influenced by partisan feelings. The next 
objection is, that it is not in the power of any man to determine, 
with any certainty, the ability of an engineer by any theoretical 
examinations. The candidate should be required to show his 
ability by practical demonstration. Another point is, that it is 
very difficult for a stranger to judge a man’s qualifications as an 
engineer, with any degree of certainty, in comparison with those 
who are in daily intercourse with him, which goes to show that, 
unless it is possible to determine to a certainty a man’s ability as 
an engineer, the license is of no value. The execution of an}^ 
license law to produce beneficial and satisfactory results should 
only be intrusted to a board of engineers, composed of theoret¬ 
ical, practical, and painstaking men — men who have performed 
all the duties incidental to the calling of an engineer. 

For this reason examinations ought to be conducted in the engine- 
and boiler-rooms, where the persons applying for certificates are 
employed, ^n that case, there would be an opportunity to test the 
candidate’s practical knowledge of everything connected with the 
engine and boilers under his charge. There can be no reason why 
jDersons, whose duty it is to inquire into the capabilities of persons 
having charge of steam-engines and boilers, should not do so on 
the premises, or on the vessels on which they are employed, as well 
as to have them go several miles, and frequently into another 
county, for that purpose. Examinations ought to be uniform in 
all localities; as, where the subjects embraced in the examination 
differ in different localities, the system is unjust. 


32 


THE ENGINEER’S HANDY-BOOK. 


There are thousands of instances on record where men, having 
charge of engines and boilers for 10 or 12 years, have secured only 
a second- or third-class certificate, simply because they were men 
of limited education, and could only imperfectly express what they 
actually knew; while others, who could furnish no positive evi¬ 
dence of ever having had charge of an engine or boiler, and who 
did not possess any of the qualifications so essential to an engineer, 
obtained first-class certificates, because they were theorists and 
good mathematicians. It is quite common to find blatant indi¬ 
viduals, who have no reputation for ability, sobriety, and industry, 
parading first-class certificates, which they obtained because they 
had abundance of assurance, while many practical and unas¬ 
suming men are almost afraid to apply for a certificate, lest they 
should be degraded to the level of a third or fourth class engineer. 
While theorists and mathematicians should receive their due meed 
of merit, it would seem unjust, so far as the awarding certificates is 
concerned, to place them above the men who, though possessing only 
a limited education, had shown by years of industry, truthfulness, 
and the successful pursuit of their calling, that they were perfectly 
reliable in every respect. These are nice points to decide, partic¬ 
ularly when it has to be done by one man, perhaps without any 
practical experience. 

The character of steam engineering can never be much ele¬ 
vated by examinations and the awarding of certificates ; the only 
hope for this lies in a law requiring every man to possess an ele¬ 
mentary knowledge of steam anxl steam machinery before being 
permitted to take charge of an engine and boiler; as, being once 
recognized as engineers, however ignorant men may be, they, as a 
general thing, evince a lack of interest in acquiring a more ex¬ 
tended knowledge of the duties of their calling. They frequently 
become too conceited to take instructions from others, or even to 
ask a question, although the answer might put them in possession 
of a fact of immense value to them. There is no reason why one 
class of men should be required to serve a regular apprenticeship, 
and even to devote years to the study of their profession, while 


THE ENGINEER'S HANDY-BOOK. 


33 


another class is allowed to discharge all the duties of a calling 
equally as important, with scarcely any preparation. 

The question is often asked, “Should an engineer be a ma¬ 
chinist?” The proper answer would be, not necessarily so; 
there is no reason why a man should learn two trades in order to 
follow one. Besides, experience has shown that, though ma¬ 
chinists are in some instances the best judges of things that may 
transpire in relation to steam machinery, they are, nevertheless, 
frequently less careful, less reliable, and less ingenious, than those 
who never learned a regular trade. Moreover, neither Savary, 
Smeaton, Watt, Stephenson, Fitch, Fulton, or either of the Ste¬ 
venses, Baldwin, or Oliver Evans were machinists. An engineer 
should be possessed of natural talent, should be ingenious and 
able to discover, any defect that may occur in the machinery under 
his charge, be able to take up the lost motion, or to take apart and 
put together the different parts of an engine. 

There is great need of reform in the use of the term engineer, 
as a customary neglect to designate to what branch of the calling 
he may belong gives rise to much inconvenience and confusion. 
A bookseller advertises a book entitled “ Hints to Young En¬ 
gineers.” Many men having charge of steam-engines order the 
book by mail, under the impression that it contains useful, if not 
valuable, information regarding their trade. On examination it 
may be found to be a treatise adapted only to young men prepar¬ 
ing themselves for the calling of civil engineers, not making a 
single allusion, or having any bearing whatever, on the business 
in which the party ordering it was engaged. Another author 
writes a book, and terms it “an Engineer’s Pocket-Book,” intend¬ 
ing it, of course, to be a hand-book for all classes of engineers, 
as in the former case; although it may contain a good deal of val¬ 
uable and useful information, it will be found, nevertheless, too 
limited to meet the requirements of any one class, as it would be 
impossible to embody such information in a book of ordinary size, 
or in any book that would come within the reach of persons of 
limited means; nor would it be possible for any author, however 

C 


34 


THE ENGINEER’S HANDY-BOOK. 


learned lie may be, to elaborate so great a variety of subjects, re¬ 
quiring, as they would, scientific accuracy and mathematical pre¬ 
cision. 

It is not uncommon to find men who have been educated as civil 
engineers, and who have devoted their lives to the pursuit of that 
calling, presuming to write treatises for the instruction of mechan¬ 
ical engineers, or men having charge of steam-engines and steam 
machinery, without possessing the first qualifications for such an 
undertaking. With the same propriety, the lawyer might write a 
treatise for the instruction of the doctor, and vice versa; or the 
doctor might attach the word squire to his name, and the lawyer 
appropriate the title of M.D. It would be more appropriate to 
use the terms, mechanical or steam engineer, civil engineer, hy¬ 
draulic engineer, dynamic engineer, sanitary engineer, etc., as, by 
the general adoption of these terms, persons wishing information 
in regard to machinery, bridges, embankments, or hydraulics, 
might consult the right person, instead of being subjected to the 
annoyance that is frequently experienced in consequence of con¬ 
sulting or engaging the services of the wrong party. Engineers 
of every class are very useful, though in different ways; their labors, 
next to that rational intellect which places man above the beast, 
have conferred on mankind the greatest boons, and the monu¬ 
ments which display the conceptions of their genius are almost as 
indestructible as the firmament or the ocean. It cannot be said 
of the engineer, as has been frequently said of the lawyer or the 
doctor, that if mankind could do without him it would be well for 
the human race. 


Facts that should he Borne in Mind by Engineers. 

No man who loves exact knowledge can fail to find scope for 
the exercise of his intellect in the calling of an engineer, as it is 
adapted to men of the most opposite temperaments. Two condi¬ 
tions alone are needed,— the man must love his work and have 
ability to perform it. 









THE ENGINEER’S HANDY- BOOK. 


35 


There is no royal road either to success or learning; the nearest 
approach to such a thoroughfare may be found in indefatigable 
study and reflection. 

A smooth sea never made a skilful mariner. Neither do unin¬ 
terrupted prosperity and happiness qualify a man for usefulness. 
The storms of adversity, like the storms of the ocean, arouse the 
faculties, and excite invention, prudence, skill, and fortitude. 

The very nature of steam engineering calls for superior intel¬ 
ligence in those on whom depend the care and management of 
steam machinery. Engineers should, therefore, prepare themselves 
for any casualty that may arise, by considering possible cases of 
derangement, and deciding in what way they would act should 
certain accidents occur. 

The strength, perfection, and durability of steam machinery 
at the present day would seem to insure perfect safety, and yet 
accidents occur when least expected, for which no amount of 
mechanical skill or forethought could provide. It is in such cases 
that the coolness, determination, and decision of the engineer may 
avert a great calamity. 

The wonderful increase in the size and speed of steamships 
and locomotives renders it absolutely necessary that, with a 
proper regard for life and property, they should be in charge of 
men of well-ascertained mental and physical abilities, as inevi¬ 
tably, sooner or later, at a critical moment, incapable men will be 
found wanting, and the most serious consequences result from their 
incapacity. 

Risks of collision, of stranding, of fire, in fact, all risks per¬ 
taining to steamships, might be very much diminished if they 
were placed in charge of intelligent men. 

The course to be pursued in an emergency must have refer¬ 
ence to particular engines, as no general rules can be given, and 
every engineer should decide on certain measures to be adopted 
in any emergency in which he may be called upon to act, where 
everything may depend upon his energy and decision. 






























































































































Steam Side of Wright’s Automatic Cut-Off Engine 
































































































































38 


THE ENGINEER’S HANDY-BOOK. 

WRIGHT’S AUTOMATIC CUT-OFF ENGINE. 

The cuts on pages 36 and 37 represent a front and back view of 
Wright’s Automatic Cut-otf high-pressure engine, the bed-plate 
or housing of which, as will be observed, is radically different 
in design and general appearance from any other in use in the 
country. The ordinary guides are dispensed with, and a guiding- 
cylinder, which is bored out on a line with the centre of the steam- 
cylinder, for the direction of movement of the cross-head, substi¬ 
tuted. There are lateral openings in the sides of the guiding- 
cylinder, through which easy access to the cross-head and piston- 
rod may be had. From the front of the guiding-cylinder to the 
point where it meets the base, the frame is made in the form of 
an inclined concavo-convex trough of sufficient depth to permit 
the free movement of the connecting-rod. The trough has the 
upper edge of one side continued in a plane coinciding with the 
centre of the cylinder, from the latter to the enlargement formed 
to receive the bearing of the crank-shaft. The opposite side of 
the trough extends from the guiding-cylinder, with a gradually 
descending curve, to the base, into the upper portion of which it 
gracefully merges. 

The steam-cylinder rests on a separate bed or foot, which sus¬ 
tains all the bearings for the valve-gear, and which is placed on 
a level with the pillow-blocks and main bed-plate, to which it is 
securely bolted and dowelled. There are four valves, two steam 
and two exhaust, which are of the gridiron or multiport-slide 
pattern. They work vertically in chests cast upon the cylinder, 
the two upon the front being for the induction cut-off and expan¬ 
sion, and those on the back for the eduction or exhaust. The 
motion for the steam- and exhaust-valves is derived from a single 
eccentric, which is so arranged as to give a quick movement to the 
valves in opening, and a slow movement when lapping. The 
stems of the steam-valves are connected with yokes having at 
their lower ends dash-pots, which act as guides. These yokes are 
operated by steel slides protruding through the ends of hollow 
rocker-arms, and acting upon the swinging toes held in the yokes. 






THE ENGINEER’S HANDY-BOOK. 


39 


The slides have a diagonal slot, in which works a feather on a rod, 
which has a longitudinal movement through the hollow rocker- 
arms with which the governor is connected. By this longitudinal 
motion through the diagonal feather and slot the slide is auto¬ 
matically set, to engage the swinging toes, more or less, according 
to requirements, to give the valve its proper lift, and release it on 
the chord of an arc. 

The governor is of a kind peculiarly adapted to these engines, 
as it is very powerful and sensitive. It rests on a bracket, or 
shelf, cast on the side of the bed-plate j the rod being connected 
with a lever which is fastened to the governor-shaft. This shaft 
carries two forked arms, which take hold of the small rods run¬ 
ning through the hollow rocker-shafts. These rods are enlarged 
at their ends, where they carry the adjustable slides which operate 
the steam-valve yokes. 

These engines are made of the best material, and fitted and 
finished in the most thorough and workmanlike manner. The 
pistons are fitted with self-adjusting steam packing-rings, the 
lower half of piston body, between the packing-rings, being fitted 
with a brass shoe, which carries the weight of the piston, and can 
be so accurately adjusted that the piston must move central with 
the bore of the cylinder. The piston-rods, wrist- and crank-pins, 
and valve-rod are made of steel, and the boxes of the best machine 
brass. The connecting-rods and crank-shafts are made of the best 
hammered iron, and the pillow-blocks are lined with anti-friction 
metal. All the rubbing, revolving, and vibrating surfaces are 
of ample proportions, and fitted with great accuracy and preci¬ 
sion. 

The Wright Engine has undergone more changes in design and 
general appearance, since it was first introduced to steam users, 
than any other engine in the country. The manufacturer seems 
to be under the impression that, however much he might alter, 
he always discovers new defects in his engine, and he appears to 
be governed more by complication and weight than by symmetry 
and convenience. Consequently, the Wright engines are heavy, 


40 


THE ENGINEER’S HANDY-BOOK. 


unsymmetrical, and expensive, and perhaps less economical than 
most other automatic cut-off engines. 

Examination of Candidates. 

The best aids to a candidate applying for an engineer’s cer¬ 
tificate are preparation, coolness, and self-possession. He must 
be prepared to answer all questions propounded to him promptly 
and without hesitation, thereby showing that he is master of the 
situation, as hesitation in answering questions will convey the 
idea that his knowledge of the subject to which they relate is 
limited. Hesitation will, in all probability, induce the examiners 
to make the examination more lengthy and rigid ; and it fre¬ 
quently happens that examinations, that might be completed in 
an hour, occupy several hours, and in some instances several days. 
Consequently, a candidate must be prepared to demonstrate prob¬ 
lems, on any subject embraced in the programme of examination, 
by formulae of his own; even if formulae and problems be given 
him, he must be prepared to demonstrate that his method is 
equally as correct, besides being more brief and simple. He 
must understand that no amount of assurance will supply the 
place of study, nor will an empty assumption of knowledge com¬ 
pensate for a defective preparation. 

Necessary Qualifications of Candidates Applying for Ap¬ 
pointments as Cadet Engineers in the U. S. Navy. 

Application may be made by candidates, or their friends, to the 
Secretary of the Navy, stating age, date of birth, educational ad¬ 
vantages, and satisfactory evidence of health and good moral 
character, which is placed on register; but neither the registering 
of names, nor priority of application, gives any assurance of ap¬ 
pointment. The number of appointments is limited by law to 
twenty-five annually. Applicants must be not under sixteen or 
over twenty years of age, and not less than five feet high. Those 
whose applications have been favorably received will be notified 


the engineer’s handy-book. 41 

to appear for examination on the 5th of September, at the Naval 
Academy. 

Candidates must be physically sound, well formed, and of 
robust constitution ; and those who possess the greatest skill and 
experience in the practical knowledge of machinery (other quali¬ 
fications being equal), shall have precedence for admission. 

The board of examiners have the power of exercising discre¬ 
tion in the application of the above requirements to each indi¬ 
vidual case, rejecting no candidate who is likely to be efficient in 
the service and admitting no one who is likely to prove physically 
inefficient. Candidates once rejected by the board of examination 
are not allowed a re-examination. 

Candidates will be rejected for any of the following causes: 
Feeble constitution; greatly retarded development; permanently 
impaired general health. All chronic diseases, viz.: Weak or 
disordered intellect; cutaneous and communicable disease ; un¬ 
natural curvature of spine, torticollis, or other deformity ; perma¬ 
nent inefficiency of either of the extremities, or articulations from 
any cause; epilepsy; impaired vision, or chronic disease of the 
organs of vision; hardness of hearing, or chronic disease of the 
ears; chronic nasal catarrh, oziema, polypi, or enlargement of 
the tonsils; impediment.of speech; indications of pulmonary dis¬ 
ease ; chronic cardiac affections; hernia; sarcocele; hydrocele; 
stricture; fistula, or haemorrhoids; varicose veins of lower limbs, 
scrotum , or cord; chronic ulcers. 

Every cadet, immediately after his admission, must supply him¬ 
self with clothing, bedding, toilet articles, sanitary utensils, etc.; 
the cost of which is $120. He must also deposit $50 with the 
paymaster, to be expended in the purchase of books, etc.; for 
which he will be credited on the books. He will also, one month 
after his admission, be credited with the amount of his expenses 
in travelling from his home to the Academy; but if he resigns 
his appointment within one year after admission, he will be re¬ 
quired to refund the amount advanced him for travelling ex¬ 
penses. 

4* 


42 


THE ENGINEER’S HANDY-BOOK. 


Examination in Grammar . 

Give the possessive singular and the objective plural of mayor, 
journey, sky, she, strife, wife. 

Answer. —Possessive singular: Mayor’s, journey’s, sky’s, her 
or hers, strife’s, wife’s. Objective plural: Mayors, journeys, skies, 
them, strifes, wives. 


Give the principal parts of smite, shed, lay, lie, drown. 


Present. 

Imperfect. 

Present Participle. 

Past Participle 

Smite, 

smote, 

smiting, 

smitten. 

Shed, 

shed, 

shedding, 

shed. 

Lay, 

laid, 

laying, 

laid. 

Lie, 

lay, 

iy in g> 

lain. 

Drown, 

drowned, 

drowning, 

drowned. 

Lie, 

lied, 

lying, 

lied. 


Compare many, cleanly, shy, little, elder, without using adverbs. 

Answer. —Many, more, most; cleanly, cleanlier, cleanliest; shy, 
shyer, shyest; little, less, least; old, older, oldest, or old, elder, eldest. 

Name the moods, and explain the use of each. 

Answer. —Infinitive expresses being, action, or passion, in an 
unlimited manner, without person or number. 

Indicative simply indicates or declares a thing. 

Potential expresses power, liberty, or necessity of being, ac¬ 
tion, or passion. 

Subjunctive represents being, action, or passion as doubtful 
or contingent. 

Imperative is used in commanding, exhorting, entreating, or 
permitting. 

“If you blow your neighbor’s fire, don’t complain if the sparks 

fly in your face.” Parse the words in dark type. 

Answer. — If is a conjunction, connecting the sentence, “don’t 
complain if the sparks fly in your face” with “you blow your 
neighbor’s fire.” 












THE ENGINEER’S HANDY-BOOK. 


43 


Blow is an irregular, active, transitive verb, subjunctive mood, 
present tense, second person, singular, to agree with its subject, 
“ you.” 

Neighbor’s is a common noun, third person, singular number, 
common gender, possessive case, governed by “ fire.” 

Don’t complain — contraction for “Do not complain” — is a 
regular, active, intransitive verb, emphatic form, in the imperative 
mood, second person, singular, to agree with its subject, “you,” 
understood, conjugated negatively. 

Your. —Your is a personal pronoun, second person, singular, 
common gender, to agree with its antecedent, “ you,” possessive 
case, governed by “ face.” 

Fire is a common noun, third person, singular number, neuter 
gender, and objective case, object of the verb “ blow.” 


Spelling . 


Commissary. 

Treasury. 

Debtor. 

Counterfeit. 

Alliance. 

Apparition. 


Identify. 

Precedent. 

Asylum. 

Levy. 

Perpetrate. 

Although. 


Anchorage. 

Correspond. 

Similar. 

Eccentric. 

Susceptible. 

Sufficient. 


Adjacent. 

Occupant. 

Weaken. 

Commercial. 

Insensible. 

Concession. 


Examination in Arithmetic . 

Express 16 days, 12 hours, 47 minutes, 25 seconds as a fraction 
of 23 days, 3 hours, 30 minutes, 23 seconds, (lowest terms.) 

d. hrs. min. sec. 


Answer. 23 3 30 23 = 1,999,823 seconds. 


d. hrs. min. sec. ■ 


16 12 47 25 = 1,428,445 “ 

1428445 

1999823 


Give the rule for finding the cube root of any number, and illus¬ 
trate by an example. 

Answer. — First. Poiut off from right to left, if an integer or 






44 


tiie engineer’s handy-book. 


whole number, and from left to right, if a decimal, in orders or 
places of three. Second. Ascertain the highest root of the first 
order, and place it to the right of the number, as in long division. 
Third. Cube the root thus found, and subtract it from the first 
order, and to the remainder annex the next order; then square 
the root already found, and multiply it by three, with two ciphers 
annexed, for a trial divisor; next find how often this divisor is 
contained in the dividend, and write the result in the root. 
Last. Add together the trial divisor, three times the product of 
the first figure of the root, by the second, with one cipher annexed, 
and the square of the second figure in the root; multiply this last 
sum by the last figure in the root, and subtract as above; to the 
remainder annex the next order, and proceed, as before directed, 
until all the orders are worked. 


To find the 4/493039. 

493039(79 
7x7x7 = 343 


7 x 7 x 3 = 14700 

150039 

7x9x3= 1890 


9x9= 81 


16671 

150039 


To find the V 403583*419. 

7x7x7 = 
7 x 7 x 3 = 14700 
7x3x3= 630 

3x3 = 9 

15339 

73 x 73 x 3 = 1598700 
73 x 3 x 3 = 19710 

9x9=_81 

1618491 


403583-419(73-9 

343 

60583 


46017 



14566419 


14566419 
















THE ENGINEER’S HANDY-BOOK. 45 

The cube of any number is that number multiplied by itself 
three times. 

Give the rale for finding the square root of any number , and 
illustrate by an example. 

Answer. — First. Point off from right to left, if an integer or 
whole number, and from left to right, if a decimal, in orders or 
places of twos. Second. Ascertain the highest root in the first 
order, and place it at the right of the number, as in long division. 
Third. Square this root, and subtract it from the first order; to 
the remainder annex the next order, and double the root already 
found, and place it to the left of this dividend. Fourth. Ascer¬ 
tain how often this divisor is contained in all but the final figure 
of the dividend, and place the quotient to the right of the root 
already obtained, and to the right of the trial divisor. Fifth. Mul¬ 
tiply this divisor by the final figure in the root, and subtract as 
before; if the remainder after a division is negative, take a figure 
for the last figure in the root one less than before, and proceed as 
directed in Fourth and Fifth. In like manner proceed until all 
the orders have been worked. 

To find the y 590’49. 

5,90-49(24-3 
4_ 

44) 190 
176 . 

483) 1449 
1449 

To find the 1 / t 075625. 

07,56,250275 

4 

47) 356 
329 

545) 2725 
2725 


Any number multiplied by itself is squared. 








46 


THE ENGINEER’S HANDY-BOOK. 


Define the terms logarithms and hyperbolic logarithms , and 
explain their use. 

Answer. —The logarithm of a number is the exponent of the 
power to which it is necessary to raise a fixed number in order to 
produce the first number. The use of logarithms is to abridge 
numerical computations. The operations of multiplication, divi¬ 
sion, involution, and evolution are very much abridged by their 
use. Any power of a given number may be found by logarithms 
as follows: The logarithm of any power of a given number is 
equal to the logarithm of the number multiplied by the exponent 
of the power. 

Example. —To find the fifth power of 9, logarithm 9 == 0 954243 
X 5 = 4*771215, and the number corresponding to this is 59049. 
Conversely. Any root of any number may be found by logarithms 
as follows: The logarithm of the root of a given number is equal 
to the logarithm of the number divided by the index of the root. 

Example. —To find the cube root of 4096, logarithm 4096 = 
3*612360 -r- 3 = 1*204120, and the number corresponding to this 
logarithm is 16. 

Hyperbolic logarithms is a system of logarithms, so called, 
because the numbers express the areas between the asymptote and 
curve of the hyperbola. The hyperbolic logarithm of any number 
is the common logarithm of the same number in the ratio of 
2*30258509 to 1, or as 1 to *43429448. 


Explain the terms geometry and trigonometry. 

Answer. —Geometry is the science of position and extension; 
that branch of mathematics which has for its object the investiga¬ 
tion of the relations, properties, and measurement of solids, sur¬ 
faces, lines, and angles. Trigonometry is that branch of mathe¬ 
matics whose object it is to determine unknown angles, or sides 
of triangles, by means of others which are known; the art or 
science of measuring triangles. It also treats of the general rela¬ 
tions existing between the trigonometrical functions of angles c" 
arcs. 




THE ENGINEER^ HANDY-BOOK. 


47 


Give the meanings of the terms quotient, product, and problem. 

Answer. —A quotient is the result of an operation in division; 
a product is the result of an operation in multiplication ; a problem 
is a question requiring some unknown truth to be demonstrated. 

Give the meanings of the terms axiom , theorem , proposition, corol- 
lary, and solution. 

Answer. —An axiom is a self-evident truth ; a theorem is a state¬ 
ment of a truth or principle which is to be demonstrated; a prop¬ 
osition is a term applied to a theorem or a problem; a corollary is 
an obvious consequence deduced from one or more propositions ; 
a solution is the result arising from any mathematical proposition 
or calculation. 

Give the names of the various triangles, their peculiarities, etc. 

Answer. —A triangle is a figure having three sides and three 
angles ; an isosceles triangle has two sides and the angles at the base 
equal; a scalene triangle has no two sides or angles equal; an obtuse- 
angled triangle has one obtuse angle in it; a right-angled triangle 
has one right angle in it; an equilateral triangle has all three sides 
and angles equal; an acute-angled triangle has one acute angle in it. 


Examination in Geography. 

i *. 

Name the States which have any coast-line on the great lakes, 
between the United States and Canada, telling in each case what 
lake the State touches. 


Answer. 

New York, 

Lakes Ontario and Erie. 

Pennsylvania, 

Lake Erie. 

Ohio, 

Lake Erie. 

Michigan, 

Lakes Erie, St. Clair, Huron, 

Indiana, 

Superior. 

Lake Michigan. 

Illinois, 

Lake Michigan. 

Wisconsin, 

Lakes Michigan and Superior. 

Minnesota, 

Lake Superior. 



48 


THE ENGINEER’S HANDY-BOOK. 


Where and on what waters are Buenos Ayres, Bordeaux, Bel¬ 
grade, Jackson, Bombay ? Tell which of the above are capitals of 
States, and of what States they are capitals. 

Answer. —Buenos Ayres is on the Rio de la Plata, and is the 
capital of the Argentine Confederation, South America; Bor¬ 
deaux is on the Garonne, in France; Belgrade is on the Danube, 
in “Turkey in Europe;” Jackson is on the Pearl River, and is 
the capital of Mississippi; Bombay is in Hindostan, Asia, on the 
coast of the Arabian Sea. 

Define the source, direction, and mouth of the Ganges River, 
Clyde River, Prutli River, Santee River. 

Answer. — The source of the river Ganges is in the Hima¬ 
laya Mountains; its direction is south-east; its mouth is in the 
north-eastern part of Hindostan, and empties into the Bay of Ben¬ 
gal. The source of the Clyde is in the Lammermoor Hills, Scot¬ 
land ; flows in a north-westerly direction, and discharges into the 
Firth of Clyde. The source of the Prutli is in the eastern base 
of the Carpathian Mountains, in Austria ; flows first east, then 
south-east, and finally south, emptying into the Danube. The 
Santee is formed by the junction of the Congaree aud Wateree 
Rivers in the central part of South Carolina; flows south-east, and 
empties into the Atlantic Ocean. 

Where is Mount Snowden, the Atlas Mountains, the Elburz 
Mountains, Mount iEtna, Mount Chimborazo? 

Answer. —Mount Snowden is a peak in the Cambrian range of 
Mountains, in Wales. The Atlas Mountains are in the “ Barbary 
States,” in Northern Africa. The Elburz Mountains are in 
Northern Persia, aud form part of the great Himalayan range. 
Mount Chimborazo is a volcano in the Andes range, in Ecuador, 
South America. 

Name five islands of the Mediterranean, define their position, 
and state to what Power each belongs. 

Answer. — The Balearic group, off the east coast of Spain, be¬ 
longs to Spain. Corsica, oft' the west coast of Italy, belongs to 


THE ENGINEER’S HANDY-BOOK. 49 

France. Sardinia, off the west coast of Italy, belongs to Italy. 
Sicily, off the south-west coast of Italy, belongs to Italy. Candia, 
or Crete, off* the south coast of Greece, belongs to Turkey. 

Examination in Natural Philosophy. 

Define centre of gravity of a body. How can the position of 
the centre of gravity of an irregular body be determined? 

Answer. —The centre of gravity of a body is the point through 
which the resultant of the weights of the several component par¬ 
ticles of a body always passes. The centre of gravity of an ir¬ 
regular body may be determined, experimentally, by suspend¬ 
ing it successively from any two points, and, after it has come 
to a state of rest, or is in equilibrium, drawing, by means of a 
plumb-line, the verticals through the points of suspension. The 
intersection of these lines will be the centre of gravity of the 
body. 

If the specific gravity of iron is 7 8 and that of gold 19-4, find 
the weight, in water, of a substance composed of one pound of iron 
and one pound of gold. 

Answer. — In this problem, first find the solid contents, in inches, 
of one pound respectively of iron and of gold, and add them. 
Then, if one cubic foot of water weighs 62'5 lbs., one cubic inch 
will weigh *036. Then multiply the combined solid contents in 
inches, of one pound of iron and gold, by the solid content in 
inches of one cubic inch of water. Thus: 

1 lb. of iron = 3*54 Cubic in. of solid contents. 

1 “ “ gold = T42 “ “ “ 

4‘96 cubic in. of solid contents of both. 

Then 4*96 x *036 = -17856. 

This product deducted from 2 lbs. will be 

2-00000 

0-17856 


5 


1-82144 

D 




50 


THE ENGINEER’S HANDY-BOOK. 


Then multiply the weight of 1 cu. ft. of water respectively by 
that of iron and gold, and dividing by 1728 we get 

62*5 x 7*8= 457*5-i-1728 = 3*54 cu. in. 

62*5 x 19*4=1212*5-r-1728 = 1*42 “ “ 

4*96 “ “ 

A cask weighing 236 lbs. 4 oz. floats in a square cistern of 
water whose side is 2 ft. 6 in. On the removal of the cask, find 
how much the water will sink in the cistern, supposing a cubic 
foot of water to weigh 63 lbs. ? 

Answer. —The weight of cask is 236 lbs. 4 oz., or, (if expressed 
decimally,) 236*25 lbs. Side of cistern is 2 ft. 6. in., or 30 inches; 
this squared equals 900 inches. Then the weight of 1 cubic 
foot of water is to 1 cubic foot of water as weight of cask is to 
cubic feet of water displaced by the cask. 

lbs. oz. ft. in. ft. in. 

236 4 = 236*25 — cistern 2 6 x 2 6 = 900 cu. in. 

lbs. cu.ft. lbs. cu. in. 

As 63 : 1 : : 236*25 : 3*75 cu. ft. 3*75 x 1728 = 6450 
and 6450 -h 900 = 7*2 in. 

How high will a common pump raise oil having a specific 

gravity of 0*88, if it raise water 33 feet? How would this height 
be affected if the force of gravity was doubled ? 

Answer. — The specific gravity of water is expressed by unity. 
Then the specific gravity of oil is to the specific gravity of water 
as the height to which water is raised is to the height to which oil 
will be raised by the same pump. 

*88 : 1 :: 33 : 37*5 ft. 

How far would a solid of any material sink into a fluid denser 
than itself? 

Answer. — On the principle that fluids become denser the 
deeper they go, a solid would sink in any fluid till it displaced 
a volume of it equal to its own density. 

Suppose the specific gravity of mercury be 14 and that of iron 
7. How far would a cubic foot of iron sink into the mercury? 



THE ENGINEER’S HANDY-BOOK. 


51 


Answer. —One-half of its volume, or, if in a normal position, 
one-half its depth. 

A cube of cork, whose edge is 1 foot, floating vertically in water, 
sinks to the depth of 2‘88 inches. Find its specific gravity. 

Answer. —First find the cubic contents of the water displaced, 
by multiplying the depth to which the cork sunk by the length 
and breadth of the same. Thus, 2‘88 X 12=41472 cu.in.; then, 
if 1728 cu. in. — 62*5 lbs., 41472 cu. in. = 15 lbs. Hence, as 
62*5 : 1000 :: 15 : 240, specific gravity of cork. 

Give the readings of Fahrenheit’s thermometer which cor¬ 
respond to 110°, 10°, 29° Centigrade; also the readings of the 
Centigrade thermometer which correspond to 77° and 23° Fah¬ 
renheit. At what temperature Centigrade will these two ther¬ 
mometers have the same readings ? 

Answer. —To change Centigrade degrees to Fahrenheit degrees, 
multiply the Centigrade degrees by 9 and divide by 5, and to the 
quotient add 32. The result is Fahrenheit degrees. 


c. 

c. 

c. 

110° 

10° 

29° 

9 

9 

9 

5) 990 

5) 90 

5) 261 

198 

18 

52-2 

32° 

32° 

'32° 

230° P. 

50° F. 

84*2° F. 


To change Fahrenheit degrees to Centigrade degrees, deduct 
32° from Fahrenheit degrees; then multiply by 5 and divide by 
9. The result is Centigrade degrees. 

Explain the meaning of the term Conic Section. 

Answer. —A conic section is a curve cut out of the surface of 
a right cone having a circular base, by a plane. The sections re¬ 
sulting from the cutting of a cone, are the triangle, the circle, the 
ellipse, the parabola, and the hyperbola; though the term conic 
section is confined to the last three. 






52 



nt View cf Woodbury, Booth & Pryor’s Automatic Cut-Of? Engine. 
























































































































































































































































































































































































Back View of Woodbury, Booth & Pryor’s Automatic Cut-Off Engin 


53 


THE ENGINEER’S HANDY-BOOK. 




















































































































































































































































































Woodbury, Booth & Pryor Automatic Cut-Off Engine. 

The cuts on pages 53 and 54 represent the Woodbury, Booth 
& Pryor Automatic Cut-off Engine. As will be observed, the bed¬ 
plate is of the girder-frame pattern, a design which has for several 
years become a favorite with engineers, both in this country and 
Europe. This perhaps arises from the fact that it affords the best 
disposition that can be made of the material to insure sufficient 
strength and rigidity, without extra weight of metal, as the centre 
frame coincides with the plane of the line of strain, and with the 
centre line of the engine. Besides, the strains induced by expan¬ 
sion and contraction can be more easily neutralized in this than 
in any other form. The frame is faced up at one end to receive 
the cylinder, the other end containing the back leg and pillow- 
block bearing. The cylinder, which is cast separate, forms a butt 
joint with the housing, and rests firmly on a handsomely designed 
hollow pedestal. 

The admission and escape of the steam is accomplished by a 
double-slide valve, as shown in Fig. 1, while the cut-off is effected 
by a semi-rotary valve, as shown in Fig. 2, located on the back 
of the steam-chest, directly over the main steam-valve; the cyl¬ 
inder in which it works being cast with the main valve. It will 
be noticed that it has diagonal admission edges, with ports to cor¬ 
respond, so that, by revolving it in its seat, it is made to cut-off 
sooner or later; the range being from zero, or nothing, to f stroke, 
according to circumstances. The steam-valve receives its motion 
in the ordinary way, from an eccentric on the main shaft, and the 
cut-off by an independent eccentric, on the rod of which is a ball 
and socket-joint, which allows the valve to rotate more or less, ac¬ 
cording to the requirements of load and pressure. The rotation, 
which never exceeds one quarter of revolution of the valve, is 
effected by a pinion on the eccentric rod, which gives motion to 
the cut-off, and into which a rack on the end of the governor- 
spindle works, which places the cut-off completely under the con- 


55 


THE ENGINEER’S HANDY-BOOK. 


trol of the governor. It would be difficult to devise any mechan¬ 
ical arrangement more simple and effective than the cut-off of 
these engines; besides, as the cut-off valve is balanced, and has a 
long bearing, there is no liability of its wearing or becoming leaky. 

The governor, which is of the fly-ball or centrifugal pattern, 



Fig. 1. 



Fig. 2. 


though of peculiar design, is admirably adapted to control the 
speed of these engines, as it is very powerful and sensitive, and 
holds the cut-off valve under complete control, under all circum¬ 
stances. The arms of the governor have their fulcrum in an 
ornamental ring, resting on four brackets, attached to the vertical 
























































































































































56 


tiie engineer’s handy-book. 


column, and, as the tilts of the arms extend across the centre, and 
have their points of suspension on the side opposite to that of the 
balls, they acquire an extensive range of movement, with a small 
variation of speed. The governor is also provided with a dash- 
pot, on the lower end of the spindle, which insures a smooth, noise¬ 
less, and uniform movement both in raising and lowering. A 
very important and agreeable feature of these engines is the ab¬ 
sence of all complication in the valves and valve-gear; there being 
only two valves, each consisting of but one piece, and all the con¬ 
nections and arrangements for adjustment being easy of access. 
Each engine is provided with a standard gauge, by which the 
valves may at any time, in case of wear, be adjusted to their 
original position, and rendered perfectly steam-tight, by any per¬ 
son of ordinary intelligence, which obviates a difficulty often ex¬ 
perienced in adjusting the valves of other steam-engines. Besides, 
as the cut-off valve and a valve-seat are cylindrical in form, they 
can be repaired or renewed at a very trifling cost, or without the 
use of any special tools. 

Some of the advantages of the Woodbury, Booth &. Pryor en¬ 
gines are, that they are handsome in design, and convenient and 
simple in arrangement; that the ports are located sufficiently low 
in the walls of the cylinder to secure perfect drainage, and obviate 
the liability of the cylinder or piston to become fractured by an 
accumulation of the water of condensation; that drip-cocks may 
be dispensed with altogether; that the pistons have the most ap¬ 
proved and convenient metallic spring packing; that the cylinders 
are handsomely jacketed, which adds to their economy by pre¬ 
venting radiation and condensation ; that the cross-head is pro¬ 
vided with convenient arrangements for easy and accurate adjust¬ 
ment; that the cranks are accurately counter-balanced, which is 
a consideration of great importance, especially in engines travel¬ 
ing at a high rate of piston speed; that the crank-pins have a 
hollow cellar or receptacle in the centre for the purpose of con¬ 
taining the lubricating material, which prevents the possibility of 
heating ; that the bottom flange of the bed-plate or housing is so 


THE ENGINEER’S HANDY-BOOK. 


57 


designed as to form a trough, which extends from the cylinder- 
head to the outer end of the pillow-block, for the purpose of 
catching the drips from the cross-head, crank, and eccentrics, 
(those from the governor and valve spindles being conducted into 
the dash-pots); that the valve and piston-rods, wrists, crank-pins, 
and crank-shafts are made of steel, thus diminishing the liability 
to wear, and likewise the expense of repairs; and that the connect¬ 
ing-rods and main journal-boxes are of ample proportions, made of 
the best material, and accurately fitted, thus insuring durability. 

The Woodbury, Booth &. Pryor engines, both automatic cut¬ 
off and throttling, are second to none in this country in point of 
durability, efficiency, and economy. They are manufactured at 
Rochester, N. Y., in any size to meet the requirements of the pur¬ 
chaser. 

i ■ 1 / 

Qualifications of Candidates for the U. S. Revenue Service. 

First. — Candidates for appointments as second assistant en¬ 
gineers must not be less than twenty-one nor more than thirty 
years of age; they must be of good moral character and correct 
habits; they must have worked not less than eighteen months in 
a steam-engine factory, or served the same period as an engineer 
on board of a steamer having a condensing engine; they must 
also produce favorable testimonials from the superintendent of 
the machine-shop, or chief-engineer of the steam-ship, as to their 
ability. 

Second. — They must be able to describe and sketch the dif¬ 
ferent parts of marine steam-engines and boilers, and explain 
their uses and mechanical movements, the method of putting 
them in operation, regulating their action, and guarding against 
danger. 

Third. — They must be fair arithmeticians and have a knowl¬ 
edge of rudimentary mechanics, be capable of writing a fair, 
legible hand, and have some knowledge of chemistry, particu¬ 
larly of combustion and corrosion. 

Fourth. — Candidates who excel in practical experience and 


58 


THE ENGINEER’S HANDY-BOOK. 


professional skill will be given the preference, both in admission 
and promotion. 

Fifth. — Any candidate producing a false certificate of age, time 
of service, or character, or making a false statement to the board 
of examiners, will be dropped from the list. 



Standard of Examination for Assistant Engineer in the 

U. S. Revenue-Cutter Service. 

First Assistant Engineer. 

First. — They must pass before the board of examiners a 

thorough examination upon the subjects prescribed for second 
assistant engineers, and be able to explain the principles, peculi¬ 
arities, functions, and uses of the different kinds of valves and 
valve-gear, as applied to marine steam machinery. 

Second.—They must understand the construction, principles, 
peculiarities, and uses of the various mechanical arrangements em¬ 
ployed in working steam expansively. 

Third. —They must understand the construction of the marine 
boilers in most general use, their attachments, and the functions 
and uses of the same. 

Fourth.—They must be able to explain the most general 
causes of derangement iu the operation of air- and feed-pumps 
and pipes, and the most practicable method of preventing and 
remedying them. 

Fifth.—They must have a knowledge of the chemical and 

mechanical causes which induce the formation of scale in steam- 
boilers, and the most practicable method of preventing and re¬ 
moving the same. 

Sixth.—They must be acquainted with the general construc¬ 
tion, principles, peculiarities, and uses of the different kinds of 
surface-condensers in present use. 

Seventh. —They must be able to calculate the loss induced 
by blowing off, for the purpose of keeping the water in the boilers 
at a uniform degree of saturation, and understand the principles 



THE ENGINEER’S HANDY-BOOK. 


59 


of the various instruments employed to determine the water’s 
saturation, as well as the method of graduating them. 

Eighth.—They must understand the principles, most practicable 
limits, and advantages of working steam expansively, and be able 
to calculate the same. 

Ninth.—They must have a knowledge of the construction of 
the indicator, know how to apply it, and intelligently explain its 
diagrams. 

Tenth.—They must be acquainted with the construction and 
the principles on which the action of steam- and vacuum-gauges 
is based, and the causes of their derangement. 

Eleventh.—They must have experience in building, erecting, 
and repairing steam machinery. 

Examinations for the Mercantile Marine Service. 

The following are among the questions most generally asked 
by examiners of engineers who apply for license in the mercan¬ 
tile marine service. 

How long have you served as a fireman ? 

How long have you served in the engine-room at sea, and in 
what capacity ? 

With what description of engines have you served at sea — 
paddle or screw, jet-condensing, surface-condensing, or non-con¬ 
densing engines, compound, trunk, inverted cylinder, or hori¬ 
zontal engines? 

What size were the engines? 

Explain the difference between condensing and non-condensing 
engines in principle and in point of economy. 

In case the pump fails to work, what course would you adopt? 
and what are the most general causes of the failure of lift, or suc¬ 
tion-bilge, or steam-pumps failing to act ? 

If the pumps fail to work, the water be low, and you are in dan¬ 
ger of being driven on a lee-shore, what course would you adopt? 

What is the object of braces in a steam-boiler? Which are 
preferable, a few large ones, or numerous small-sized ones? 




60 THE ENGINEER’S HANDY-BOOK. 

What parts of a marine engine are most likely permanently to 

disable the ship in case of breakage? 

Demonstrate by example (taking your own data) the safe 
working and bursting pressure of a boiler. 

Demonstrate by example (taking your own data) the load 
necessary to be placed on the lever of a safety-valve for a given 
pressure of steam. 

With what description of boilers have you served at sea — 
wet-bottomed, dry-bottomed, multi-tubular, sectional or flue, water- 
or fire-tube boilers ? 

What engine defects have come under your notice at sea? 
What caused those defects? How were they remedied? Give 
the names of the steamers. 

What boiler defects have come under your notice at sea? 
What caused those defects? 

How were they remedied ? Give the names of the steamers. 

Qualifications of Stationary Engineers. 

In locations where the law requires persons having charge of 
stationary steam-engines to procure certificates of competency, the 
examination generally embraces the following subjects: 

First.—Whether the candidate has charge of an engine at 
present. If not, where he had charge of one last. If he has a 
recommendation from his last employer. What was the size of 
the engine of which he had charge, diameter of cylinder, stroke, 
travel of piston, pressure as shown by the steam-gauge, etc., and 
what power such an engine was capable of developing. 

Second. — Whether the engine was condensing or non-con¬ 
densing, horizontal, vertical, inclined, oscillating, trunk, or beam, 
and the difference between a condensing and a non-condensing 
engine. 

Third. —Whether the engine was automatic, cut-off or slide, 
throttling- or poppet-valve, and the difference between an auto¬ 
matic cut-off and slide-valve throttling-engine. 

Fourth. — What he would consider his first duty on entering 




THE ENGINEER’S HANDY-BOOK. 


61 


the engine-room after being absent, or on taking charge of an 
engine and boiler for the first time. How lie would proceed to 
set a slide-valve. How he could tell, without examining the 
valve, whether the engine was exhausting regularly or not, and 
what he would do before starting .an engine, if it had been stand¬ 
ing still for some time, particularly in cold weather. 

Fifth.—Whether the boilers he had charge of were plain cylin¬ 
der, flue, tubular, tubulous, or fire-box; whether they were in¬ 
ternally or externally fired ; and whether, on any occasion, he 
ever fired up under a boiler and afterwards discovered there was 
insufficient water in it. 

Sixth.—What advantages and disadvantages do plain cylinder, 
flue, tubular, tubulous, and fire-box boilers possess over each other 
in point of economy of fuel, efficiency, safety, durability, and 
space ? 

Seventh. — How often should a boiler be cleaned, and how 
should it be managed before cleaning? How often ought boilers 
to be examined, and what should be the character of such an ex¬ 
amination? What are the object and nature of the different tests 
now employed, and their effect on the boiler '( 

Eighth. — What course lie would pursue in case the feed-water 
was cut off for a short time, or what would he do if cut off for an 
indefinite period, or from any cause became dangerously low; 
how he would proceed if obliged to stop his engine when steam 
was blowing off at the safety-valve and a heavy fire in the fur¬ 
nace ; and how he would regulate his fire, when starting to raise 
steam, with cold water in the boiler. 

Ninth.—The difference in the strains to which the shell, flues, 
tubes, crowns, and other parts of steam-boilers are subjected, as 
well as those which the longitudinal and curvilinear seams have 
to bear; also the difference in strength between single- and double- 
riveted seams, the loss induced by punching or drilling the holes 
for the rivets, and the difference in strength between punched and 
drilled holes, and between hand and machine riveting. 

Tenth. — The diameter and length of the boiler of which he 
6 


62 


THE ENGINEER’S HANDY-BOOK. 


had charge last; the diameter and length of the tubes or flues; 
the thickness of the shell; the number of square feet of heating 
surface in it — also of grate surface; the area of the safety-valve, 
and whether the boiler was single or double riveted. 

Eleventh.—The safe working- and bursting-pressure of boil¬ 
ers, single or double riveted, of different diameters and of different 
thicknesses of iron; the proportions of grate and heating surfaces 
that would be capable of generating sufficient steam to develop a 
horse-power; and the orifice of safety-valve that would liberate 
that quantity of steam, provided that all other means of escape 
were closed. 

Twelfth. — A demonstration, from his own data, of the weight 
necessary to place on the safety-valve for a given pressure when 
the length of the lever and the area of the safety-valve are known ; 
also the pressure required to lift a certain weight, with a given 
length of lever and area of valve. 

Thirteenth. — What are the most probable causes of lift or 
suction, force or boiler feed-pumps failing to work? 

Locomotive Engineers. 

Locomotive engineers are not required to furnish evidence that 
they possess any theoretical knowledge; nor are they required to 
pass any examination. They are all employed in the first place as 
firemen or brakemen, and their promotion to the charge of a loco¬ 
motive depends on their sobriety, industry, and endurance. On 
most railroads they are required to fire from two to three years; 
after which, if they give evidence of sufficient capacity and care¬ 
fulness, they are generally placed in the repair-shop or round¬ 
house for one year, to enable them to learn the use of tools, but 
more particularly to make them acquainted and familiar with the 
construction of the locomotive engine, and the manner of taking 
its machinery apart and putting it together again. 

If, at the end of three or four years, he has conducted himself 
properly, and given sufficient evidence of his knowledge of the 
construction of a locomotive engine and its management to make 


THE ENGINEER’S HANDY-BOOK. 63 

a good engineer, lie is promoted to a third-class engineer. After 
one year’s trial as third-class engineer, if he still gives evidence 
of capacity and carefulness, he is advanced to the position of 
second-class. If, after the expiration of one year as a second- 
class engineer, he is qualified in every way for a first-class en¬ 
gineer, he is advanced to that grade; but if not found competent, 
he is considered out of the regular order of promotion. 

Steam. 

Steam is an elastic fluid resulting from the combination of heat 
with water, and, when the steam is not in contact with the water 
from which it is formed, it follows the same general law as all 
other gases. This law is as follows: All gases expand by heat 4 
part of their volume for every degree Fall., while their elastic 
pressure remains unaltered, and so long as the temperature of a 
gas remains unaltered, its elastic pressure will vary inversely to 
the volume. Steam is of several kinds. Surcharged steam is 
steam heated to a temperature higher than is due to its pressure. 
Saturated steam is steam which, in contact with the fluid from 
which it is formed, has brought with it a proportion of moisture. 

Supersaturated steam is steam in which there is more water 
mingled in the form of minute spray than is generally contained 
in saturated steam, which is called the water of supersaturation. 

The temperature of the steam is always equal to that of the 
water from which it is formed, and the elastic force of steam 
formed is equal to the pressure under which it is formed. The 
elastic force of steam, barometer at 30°, at 212° Fall., is one at¬ 
mosphere, or 14*7 lbs. per sq. inch; while at 250° Fah. its elastic 
force is two atmospheres, or 29*4 lbs. per sq. inch. This includes 
the pressure of the atmosphere. 

If the mercury be in a vacuum, the pressure of steam due to a 
temperature of 212° Fah. will equal 30 inches, and for a pressure 
due to a temperature of 250° Fah. it will equal 60 inches; but 
if the mercury be exposed to the atmosphere, the pressure due to 
250° Fah. will only equal 30 inches of mercury, and for 212° 


^4 


THE ENGINEER’S HANDY-BOOK. 


Fah. there is no indication by a mercury gauge, as steam at 212° 
just balances the atmosphere. 

The volume of steam is the space which it occupies. At 15 
lbs. pressure above atmosphere, its volume is 883, and at 30 lbs. 
its volume is 610 times the space it occupied in the shape of 
water. 

Surcharged steam is not indicated by the steam-gauge, as the 
steam-gauge only shows the existence of pressure; but it may be 
indicated by a thermometer gauge, or by a fusible plug. 

If the proper relation of the temperature between the steam and 
water be disturbed, a violent ebullition or foaming will generally 
take place, and will continue till the natural relation is restored. 
This foaming is a source of danger to the engine and boilers. 

The total heat of steam at 212° Fah. is 1202°, of which 990° 
are latent heat, which is heat that is neither sensible to the touch, 
nor can it be indicated by the thermometer. The existence of 
this latent heat in water, while in the form of steam, may be 
proved by the following illustration: If 5 2 lbs. of water, at 32° 
Fah., are placed in a vessel communicating with another, in which 
water is kept at 212° Fah., and kept there till the former reaches 
a temperature of 212° Fall., and then weighed, it will be found 
to weigh 61 lbs., showing that 1 lb. of water has been added to 
the 5s lbs. in the form of steam. This pound of water, received 
in the form of steam had, when in that form, a temperature of 
212° Fah. It still possesses the same temperature of 212° Fall., 
showing that it has parted with 51 times the number of degrees 
of temperature between 32° and 212 3 , which is 180, and 51x180 
= 990°. This heat was combined with the steam, but not being 
sensible to the thermometer is called latent; in this connection 51 
is taken as a convenient number. 

If we observe the time that a certain amount of heat takes to 
raise water from 32° to 212°, no matter what the time may be, it 
will take 51 times as long for the same heat to evaporate the same 
amount of water. It follows, that to evaporate water under the 
pressure of the atmosphere requires 51 tim^s as much heat as 







THE ENGINEER’S HANDY-BOOK. 65 

would be necessary to raise the same amount of water from 32° 
to 212 °. 

A pound of steam in passing from a liquid at 212° to steam at 
212 ° receives as much heat as would be sufficient to raise it 
through 990°, if that heat, instead of being latent, had been sen¬ 
sible, and 990° -f 212 = 1202° is the whole amount of the heat 
in steam. 

The latent heat of steam is found by deducting its sensible heat 
from 1202 °. 

TABLE 


SHOWING THE INCREASE OF SENSIBLE AND THE DECREASE OF LATENT 
HEAT IN STEAM, ACCORDING TO PRESSURE. 


Gross Pressure. 

Sensible Heat. 

Latent Heat. 

Relative Volume. 

15 lbs. 

212 ° 

966-2° 

1669 

30 “ 

251° 

9390° 

881 

45 “ 

275° 

922-7° 

608 

60 “ 

294° 

909-2° 

467 

75 “ 

309° 

898-5° 

381 

90 “ 

320° 

891-3° 

323 


Heat in steam becomes latent whenever a change takes place 
in the temperature; then the heat produces the change, but does 
not raise the temperature. 

The heat necessary to generate steam, instead of being 212°, 
must be 966 -j- 212° = 1178° ; therefore, the coal consumed and 
the water necessary to condense the steam must be 51 times as 
great as they would be, if the heat were all sensible instead of 
latent, which, it will be observed, very materially affects the econ¬ 
omy of the steam-engine. 

The amount of water necessary to condense a certain quantity 
of steam may be found as follows: If a cubic inch of water pro¬ 
duces a cubic foot of steam, and the latent heat of steam at 212 ° 
be taken at 990°, or, in other words, if the cubic foot of steam be 
supposed to contain as much heat in the latent form as would 
raise the temperature of the cubic inch of water, if it could be 
6 * E 










66 


THE ENGINEER^ HANDY-BOOK. 


prevented from expanding, then 990°, the sum of the latent heat, 
will be represented by 1202°. The temperature of the water dis¬ 
charged by the air-pump is about 100°, which, deducted from 
1202 °, leaves 1102°, which must be taken up by such a quantity 
of cold water that its temperature will not rise above 100°. If 
the temperature of the injection-water be 50°, then the difference 

between that and 100° is 50°, which is available for the absorp- 

1102 ° 

= 22T, which is the number of times the 


tion of heat, and 
injection-water must exceed the quantity of water in the steam. 


Inasmuch as the injection-water is seldom so cold, a much larger 
proportion of injection-water is usually required. 

Steam which has any elastic force not exceeding that of one 
atmosphere is termed “low pressure” steam, and “high pressure” 
is only low pressure steam compressed into a smaller space. 

Surcharged steam will affect the vacuum of an engine on 
account of the undue amount of heat which it contains; there¬ 
fore, the amount of injection-water must be increased to take up 
this extra heat, and keep the condensed water at the proper tem¬ 
perature. 

The steam from salt water is fresh, because no salt is carried 
away in the steam when evaporation from salt water takes place; 
and when the water is all evaporated, the original salt will be 
found in the vessel. 

The difference in volume between water and steam at atmos¬ 
pheric pressure is 1669; that is, a given quantity of water, when 
converted into steam, will occupy 1669 times that which the water 
did. One cubic foot of steam, at atmospheric pressure, weighs 
*038 of a pound. 

A steam-jacket is a hollow casing surrounding the cylinders of 
steam-engines, into which the exhaust steam is admitted in its 
escape from the cylinder. Its object is to preserve a uniform 
temperature, and to prevent radiation and condensation. The 
benefit to be derived from its use, in any case, is an unsettled 
question among engineers. 






f 



THE ENGINEER’S HANDY-BOOK. 67 

TABLE 


SHOWING THE EFFLUENT VELOCITY WITH WHICH STEAM, AT DIFFERENT 
PRESSURES, WILL FLOW INTO THE ATMOSPHERE, OR INTO STEAM AT A 
LOWER PRESSURE. 


Pressure above 
the Atmosphere. 

V elocity of Escape 
per Second. 

Pressure above 
the Atmosphere. 

Velocity of Escape 
per Second. 

Pounds. 

Feet. 

Pounds. 

Feet. 

1 

540 

50 

1736 

2 

698 

60 

1777 

3 

814 

70 

1810 

4 

905 

80 

1835 

5 

981 

90 

1857 

10 

1232 

100 

1875 

20 

1476 

110 

1889 

30 

1601 

120 

1900 

40 

1681 

130 

1909 


Rule for Finding the Amount of Gain derived from Work¬ 
ing Steam Expansively. 

Divide the length of the stroke in feet by the cut-off, i, 1, 4, as 
the case may be; then find on the table on page 68 the hyperbolic 
logarithm nearest to that of the quotient, to which add 1 . This 
sum will give the ratio of gain. 

Example. —Suppose 50 pounds per square inch to be the ini¬ 
tial pressure; length of stroke, 10 feet; cut-off, 1 ; find the mean 
pressure. 

10 -r- 2*5 == 4. The hyperbolic logarithm of 4 is T38629, which, 
with 1 added, becomes 2*38629, which is the ratio of gain. 

2-28699 v 50 

4 : 2*38629 :: 50 =---= 29*82862 lbs. mean or aver- 

4 

age pressure. 

If a given quantity of Steam, the expansive power of which, at 
full pressure, is represented by 1 , be admitted to a cylinder of a 
certain size, and cut off when the piston travels through \ of the 
stroke, its effect will be raised by expansion to 1*69; if cut off at 
4, the effect will be 2*10; at 1, 2*39; at 4, 2*61; at c, 2*79; at 1, 
2*95 ; at £, 3*08 ; but the expansion cannot be carried beneficially 
as far as l in all classes of engines. 












68 


THE ENGINEER’S HANDY-BOOK. 


TABLE 

OF HYPERBOLIC LOGARITHMS TO BE USED IN CONNECTION WITH THE 

ABOVE RULE. 


No. 

Logarithm. 

No. 

Logarithm. 

No. 

Logarithm. 

1-25 

•22314 

5- 

1-60943 

9- 

2-19722 

1-5 

•40546 

525 

1-65822 

95 

2-25129 

1-75 

•55961 

5-5 

1-70474 

10- 

2-30258 

2- 

•69314 

575 

1-74919 

11- 

2-39789 

225 

•81093 

6- 

1-79175 

12- 

2-48490 

2 5 

•91629 

6‘25 

1-83258 

13- 

2-56494 

275 

1-01160 

6 5 

1-87180 

14- 

2 63905 

3- 

109861 

675 

1-909.54 

15* 

2-70805 

325 

1-17865 

7- 

1-94591 

16- 

2-77258 

35 

1-25276 

725 

1-98100 

17- 

2-83321 

375 

1-32175 

7-5 

2-01490 

18- 

2 89037 

4- 

1-38629 

7-75 

2-04769 

19- 

294443 

425 

1-44691 

8‘ 

2 07944 

20- 

299573 

45 

1*50507 

85 

214006 

21- 

3 04452 

475 

1-55814 



22- 

309104 


Rule for finding the mean or average pressure in the cylinder 
of a steam-engine. 

Divide the length of the stroke in inches (including the clear¬ 
ance) by the distance that the steam follows the piston before 
being cut off; the quotient will be the expansion the steam under¬ 
goes. Then find in the expansion column, in the following table, 
the number corresponding to it; take the multiplier opposite, and 
multiply the full pressure of the steam per square inch, as it enters 
the cylinder, by it. The product will be the average pressure. 

Example. —Suppose the initial pressure be 70 lbs. per sq. inch 
and cut-off at half-stroke, the stroke being 3 ft. 

Then 3 ft. = 36 in. -j- 0*5 for clearance — 36*5. 

Stroke £ = 18 in. -f 0 5 “ = 18*5. 

Then 36*5 h- 18*5 — 1*97, the relative expansion between 1*9 
and 2. By referring to the table, the multiplier for 1*9 will be 
found to be 0*864, and the difference between that and the multi¬ 
plier for 2 is 0*017. Hence, by multiplying 0*017 by *07, and 
subtracting the product 0*011, the remainder, 0*86281, is the mul¬ 
tiplier for 1*97. Therefore, 0*86281 x 70 = 60*3967 lbs. per sq. 
inch, the mean effective pressure on the piston. 


















THE ENGINEER’S HANDY-BOOK. 69 

TABLE 

OF MULTIPLIERS BY WHICH TO FIND THE MEAN PRESSURE OF STEAM AT 


VARIOUS POINTS OF CUT-OFF. 


Expansion. 

Multiplier. 

Expansion. 

Multiplier. 

Expansion. 

Multiplier. 

1*0 

1*000 

3*4 

*654 

5*8 

•479 

IT 

•995 

3-5 

•644 

5-9 

*474 

1*2 

•985 

3*6 

•634 

6 * 

*470 

1*3 

•971 

3-7 

•624 

6-1 

*466 

1-4 

•955 

3-8 

* 615 . 

6-2 

•462 

1*5 

•937 

3*9 

•605 

6*3 

•458 

1*6 

•919 

4 ’ 

*597 

6*4 

•454 

1*7 

•900 

4*1 

•588 

6-5 

•450 

1*8 

•882 

4-2 

*580 

6*6 

•446 

1-9 

*864 

4-3 

•572 

6*7 

•442 

9* 

•847 

4-4 

*564 

6*8 

•438 

2 T 

*830 

4-5 

•556 

6*9 

•434 

2-2 

•813 

4*6 

•549 

7 * 

•430 

2-3 

*797 

4'7 

•542 

71 

•427 

2 T 

*781 

4*8 

•535 

7*2 

•423 

2-5 

*766 

4-9 

•528 

7-3 

•420 

2-6 

*752 

5 * 

*522 

7*4 

•417 

2*7 

•738 

5 T 

•516 

7*5 

•414 

2-8 

•725 

5-2 

•510 

7*6 

•411 

2*9 

*712 

5-3 

*504 

7-7 

•408 

3 * 

*700 

5'4 

•499 

7*8 

•405 

3 T 

•688 

5*5 

•494 

7*9 

•402 

3*2 

*676 

5-6 

•489 

8 * 

•399 

3*3 

•665 

57 

•484 




TABLE 


OF CONSTANT NUMBERS, BY WHICH TO ASCERTAIN THE AVERAGE PRESS¬ 
URE OF THE STEAM AGAINST THE PISTON FOR DIFFERENT PRESSURES 
AND POINTS OF CUT-OFF, FROM \ TO f- OF THE STROKE. 


Point of Cut-off. 

Constant Number. 

Point of Cut-off. 

Constant Number. 

1 

4 

•5965 

5 

s' 

•9188 

1 

3 

•6995 

2 

3 

•9870 

3 

g 

•7428 

3 

4 

•9657 

1 

Jg 

•8465 

7 

5 

•9919 


Multiply the pressure in pounds, as shown by the gauge, by the 
constant number opposite the point of cut-off in the left column. 
The product is the average pressure. 































70 


THE ENGINEER’S HANDY-BOOK. 


TABLE 


OF CONSTANT NUMBERS FOR FINDING THE REQUIRED “LAP” FOR SLIDE- 
VALVES, WHEN THE TRAVEL OF THE VALVE IS KNOWN. 


Cut-off._ 

1 

2 

7 

T2 

2 

3 

3 

4 

5 

6 

7 

8 

11 
12 

Multiplier. 

•354 

*323 

•289 

•250 

•204 

T77 

•144 


Multiply the valve-stroke by the decimals opposite each point 
of cut-off. 

There are two methods of applying the power of steam to the 

cylinders of steam-engines, one being to allow it to flow from the 
boiler to the cylinder through the whole length of the stroke, the 
other to cut off the supply when the piston has travelled a certain 
distance. The advantage of the latter over the former consists 
in the saving of fuel; which may be explained as follows: If 
steam be applied the full length of the stroke, the average press¬ 
ure will be as the pressure per square inch on the piston; but if 
the steam be cut off* at half stroke,— suppose the pressure to be 
65 lbs. per square inch, when the pressure of the atmosphere is 
added,— there will be a mean equivalent, or average pressure, 
throughout the stroke of about 55 lbs. per square inch, being only 
10 lbs. less than full pressure, or 16 per cent, of a loss in power, 
though only half the former quantity of steam has been used. 

Steam-ports. — A term applied to the passages through which 
the steam enters the cylinder; they are generally ^ the area of 
the piston, but vary for different boiler pressures and piston speeds, 
those of locomotives being about T Y,, which have the largest ports 
of any class of engines. The area of the exhaust-port should be 
from to that of the cylinder. As a rule, the exhaust, when 
passing out of the cylinder after the first rush is over, should not 
have to travel faster than 100 feet per second ; but with some de¬ 
signs of engines the velocity of the steam may be greater, without 
creating injurious back pressure. The form of the ports is imma¬ 
terial, providing they are large enough to give admission to the 
amount of steam requisite to keep the pressure up to its initial point 
until it is cut off by the valve, and give free egress for its escape. 











71 


THE ENGINEER’S HANDY-BOOK. 


TABLE 

SHOWING THE AVERAGE PRESSURE OF THE STEAM UPON THE PISTON 
THROUGHOUT THE STROKE, WHEN CUT OFF IN THE CYLINDER FROM 
| TO COMMENCING WITH 10 POUNDS AND ADVANCING IN 5 POUNDS 
UP TO 55 POUNDS PRESSURE. 


Steam cut off 
in the 
Cylinder. 

Pressure in Pounds at the Commencement of the Stroke. 

10 

15 

20 

25 

30 

35 

40 

45 

50 

55 

Average Pressure in Pounds upon the Piston. 

l 

3 

7 

101 

141 

171 

21 

241 

28 

311 

35 

381 

2 

3 

91 

14 

181 

231 

281 

321 

371 

42 

461 

511 

1 

4 

6 

9 

12 

15 

171 

201 

231 

261 

291 

321 

1 

2 

81 

121 

17 

21 

251 

291 

331 

38 

421 

461 

3 

4 

91 

141 

191 

24 

281 

331 

381 

431 

481 

53 

1 

7 

51 

71 

101 

13 

151 

181 

201 

231 

26 

281 

O 

5 

71 

111 

151 

19 

23 

261 

301 

341 

381 

42 

3 

9 

13 

18 

221 

27 

311 

361 

401 

451 

491 

4 

9! 

141 

191 

231 

291 

341 

39 

44 

49 

531 

1 

A 

41 

7 

91 

111 

14 

161 

181 

201 

231 

251 

5 

91 

141 

191 

241 

291 

341 

391 

441 

491 

54 

1 

*7" 

41 

61 

81 

101 

121 

141 

161 

181 

21 

231 

2 

61 

91 

121 

16 

191 

221 

251 

281 

32 

351 

7 

3 

& 

71 

111 

151 

191 

231 

271 

311 

351 

391 

431 

7 

4 

w 

81 

131 

171 

221 

261 

311 

351 

40 

441 

49 

7 

5 

-fr 

91 

141 

19 

231 

281 

331 

381 

421 

471 

521 

i 

G 

y=r 

91 

141 

191 

241 

291 

341 

391 

441 

491 

541 

i 

JL 

31 

51 

71 

91 

111 

131 

151 

171 

191 

211 

8 

3 

71 

11 

141 

181 

221 

26 

291 

331 

37 

401 

8 

5 

91 

131 

181 

221 

271 

32 

361 

411 

451 

501 

8 

i 

91 

141 

191 

241 

291 

-f 

CO 

391 

441 

491 

541 







































72 


THE ENGINEER^ HANDY-BOOK 


TABLE 

SHOWING THE AVERAGE PRESSURE OF THE STEAM UPON THE PISTON 
THROUGHOUT THE STROKE, WHEN CUT OFF IN THE CYLINDER FROM 
| TO COMMENCING WITH 60 POUNDS AND ADVANCING IN 5 POUNDS 
UP TO 105 POUNDS PRESSURE. 


to 

° * 

0) 0> 


1 

Pressure in Pounds at the Commencement of the Stroke. 












g S3 
OH* 

a> 

GO 

60 

65 

70 

75 

80 

85 

90 

95 

100 

105 

Average Pressure in Pounds upon the Piston. 

1 

3 

42 

45* 

49 

52* 

56 

59* 

63 

66 * 

70 

73 

2 

3 

56* 

61 

65* 

70* 

75 

79* 

84* 

89 

93! 

98* 

1 

4 

351 

38| 

41! 

44! 

47! 

50! 

53! 

56! 

59! 

62! 

1 

50f 

55 

59* 

63* 

67! 

72 

76* 

80* 

84! 

89 

3 

4 

57 f 

62* 

67* 

72* 

77* 

82 

87 

91! 

96* 

101 * 

1 

T> 

31* 

34 

36* 

39 

41! 

44* 

47 

49* 

52* 

54! 

2 

5 

46 

49| 

53* 

57* 

61* 

65 

69 

72! 

76* 

80* 

3 

5 

54* 

581 

63* 

67! 

72* 

77 

81* 

86 

90* 

95* 

4 

¥ 

58* 

63* 

68 * 

73! 

78* 

83 

88 

92! 

97! 

102 ! 

1 

6 

271 

30* 

32* 

34! 

37* 

39* 

41! 

44* 

46* 

48! 

5 

6 

59 

64 

69 

73! 

OO 

83! 

88 ! 

93* 

98* 

103* 

1 

T 

25* 

27* 

29* 

31* 

33* 

35! 

* 

CO 

40 

42 

44 

2 

T 

38* 

41! 

45 

48* 

51* 

54* 

57! 

61 

64* 

67* 

3 

1 

47* 

51* 

55£ 

59* 

63* 

67* 

71* 

75* 

79 

83 

4 

53* 

57 f 

62* 

66 ! 

71* 

75! 

80 

84* 

89 

93* 

j 

b 

T 

57* 

62 

66 ! 

71* 

76* 

81 

85! 

90! 

95* 

100 * 

6 

1 

59* 

631 

69* 

74* 

79 

84 

89 

93! 

98! 

103! 

1 

8 

23 

25 

27 

28! 

30! 

32! 

34* 

36* 

38* 

40* 

3 

¥ 

44* 

48* 

52 

55! 

59* 

63 

66 ! 

70* 

74* 

78 

5 

8 

55* 

59! 

64^ 

68 ! 

73* 

78 

82* 

87* 

91! 

96* 

7 

8 

59* 

64* 

69^ 

74* 

79* 

84* 

89* 

94* 

99 

104 














































73 


THE ENGINEER’S HANDY-BOOK. 


TABLE 

SHOWING THE AVERAGE PRESSURE OF THE STEAM UPON THE PISTON 
THROUGHOUT THE STROKE, WHEN CUT OFF IN THE CYLINDER FROM 
-j TO COMMENCING WITH 110 POUNDS AND ADVANCING IN 5 POUNDS 
UP TO 150 POUNDS PRESSURE. 


SB 

® t." 

-B « 

° «-* B 

B 

Pressure in Pounds at the Commencement of the Stroke. 

110 

115 

120 

125 

130 

135 

140 

145 

150 

03 ,*7 

CD 

ai 

Average Pressure in Pounds upon the Piston. 

1 

3 

77* 

801 

84 

871 

91 

941 

98 

1011 

105 

Q 

3 

103 

1071 

1121 

117 

1211 

1261 

131 

1351 

1401 

i 

4 

65 i 

681 

711 

741 

771 

801 

831 

861 

891 

1 

2 

93 i 

971 

1011 

1051 

110 

1141 

1181 

1221 

127 

3 

4 

1061 

111 

1151 

1201 

1251 

1301 

1351 

140 

1441 

1 

z 

571 

i 

60 

621 

651 

67} 

701 

73 

751 

781 

2 

5 

841 

88 

911 

951 

991 

1031 

1071 

111 

115 

3 

5 

991 

1041 

1081 

113} 

1171 

1221 

1261 

1311 

135 

4 

5 

1071 

1121 

1171 

1221 

1271 

132 

1361 

1411 

1461 

i 

e 

511 

531 

551 

58 

601 

621 

65 

671 

691 

5 

1081 

1131 

1181 

1231 

128 

133 

1371 

1421 

147 

i 

T 

461 

481 

501 

521 

541 

561 

581 

61 

63 

2 

7 

701 

74 

771 

801 

831 

861 

90 

931 

961 

3 

T 

87 

91 

941 

981 

1021 

1061 

1101 

1141 

1181 

4 

T 

98 

1021 

1061 

mi 

1151 

1201 

1241 

1291 

1331 

5 

105 

1091 

1141 

1191 

124 

1281 

1331 

1381 

1431 

6 

7 

108} 

1131 

1181 

1231 

1281 

1331 

1381 

1431 

1481 

1 

S 

421 

441 

461 

48 

50 

52 

541 

561 

571 

3 

IT 

811 

851 

89 

921 

961 

1001 

104 

1071 

mi 

5 

101 

1051 

1101 

1141 

1191 

124 

1281 

1331 

1371 

7 

8 

109 

114 

119 

124 

1281 

1331 

1381 

1431 

1481 


7 


































74 


THE ENGINEER^ HANDY-BOOK. 

TABLE 

SHOWING THE TEMPERATURE OF STEAM AT DIFFERENT PRESSURES, FROM 
1 LB. PER SQUARE INCH TO 220 LBS., AND THE QUANTITY OF STEAM 
PRODUCED FROM A CUBIC INCH OF WATER, ACCORDING TO PRESSURE. 


It is necessary to add the pressure of the atmosphere. 15 pounds, to the pressure on 
the steam-gauge, to correspond with the table. 


Total 
Pressure 
of Steam 
in lbs. per 
Square 
Inch. 

Correspond¬ 
ing Temper¬ 
ature of 
Steam to 
Pressure. 

Cubic Inches 
of Steam from 
a Cubic Inch 
of Water 
according to 
Pressure. 

Total 
Pressure 
of Steam 

I in lbs. per 
Square 
Inch. 

Correspond¬ 
ing Temper¬ 
ature of 
Steam to 
Pressure. 

Cubic Inches 
of Steam from 
a Cubic Inch 
of Water 
according to 
Pressure. 

1 

102 * 9 ° 

20868 

29 

249 - 6 ° 

911 

2 

126-1 

10874 

30 

251-6 

883 

3 

141-0 

7437 

31 

253-6 

857 

4 

152-3 

5685 

32 

255-5 

833 

5 

161*4 

4617 

33 

257-3 

810 

6 

169-2 

3897 

34 

259*1 

788 

7 

175-9 

3376 

35 

260*9 

767 

8 

182-0 

2983 

36 

262-6 

748 

9 

187*4 

2674 

37 

264-3 

729 

10 

192*4 

2426 

38 

265-9 

712 

11 

197-0 

2221 

39 

267-5 

695 

12 

201*3 

2050 

40 

269*1 

679 

13 

205-3 

1904 

41 

270-6 

664 

14 

209-1 

1778 

42 

272-1 

649 

15 

212*8 

1669 

43 

273-6 

635 

16 

216-3 

1573 

44 

275-0 

622 

17 

219-6 

1488 

45 

276-4 

610 

18 

222-7 

1411 

46 

277*8 

598 

19 

225-6 

1343 

47 

279-2 

586 

20 

228-5 

1281 

48 

2805 

575 

21 

231-2 

1225 

49 

281-9 

564 

22 

233*8 

1174 

50 

283-2 

554 

23 

236-3 

1127 

51 

284-4 

544 

24 

238-7 

1084 

52 

285-7 

534 

25 

241-0 

1044 

53 

286-9 

525 

26 

243-3 

1007 

54 

288-1 

516 

27 

2455 

973 

55 

289-3 

508 

28 

247-6 

941 

56 

290-5 

500 























75 


THE ENGINEER’S HANDY-BOOK. 

x 

TABLE 

SHOWING THE TEMPERATURE OF STEAM AT DIFFERENT PRESSURES, FROM 
1 EB. PER SQUARE INCH TO 220 LBS., AND THE QUANTITY OF STEAM 
PRODUCED FROM A CUBIC INCH OF W'ATER, ACCORDING TO PRESSURE. 


It is necessary to add the pressure of the atmosphere, 15 pounds, to the pressure on 
the steam-gauge, to correspond with the table. 


Total 
Pressure 
of Steam 
in lbs. per 
Square 
Inch. 

Correspond¬ 
ing Temper¬ 
ature of 
Steam to 
Pressure. 

Cubic Inches 
of Steam from 
a Cubic Inch 
of Water 
according to 
Pressure. 

Total 
Pressure 
of Steam 
in lbs. per 
Square 
Inch. 

Correspond¬ 
ing Temper¬ 
ature of 
Steam to 
Pressure. 

Cubic, Inches 
of Steam from 
a Cubic Inch 
of Water 
according to 
Pressure. 

57 

291 - 7 ° 

492 

85 

320 - 1 ° 

342 

58 

292*9 

484 

86 

321'0 

339 

59 

294-2 

477 

87 

321-8 

335 

60 

295*6 

470 

88 

322-6 

332 

61 

296*9 

463 

89 

323-5 

328 

62 

298*1 

456 

90 

324-3 

325 

63 

299*2 

449 

91 

325-1 

322 

64 

300-3 

443 

92 

325-9 

319 

65 

301-3 

437 

93 

326*7 

316 

66 

302*4 

431 

94 

327-5 

313 

67 

303-4 

425 

95 

328*2 

310 

68 

304-4 

419 

96 

329-0 

307 

69 

305'4 

414 

97 

329-8 

304 

70 

306*4 

408 

98 

330-5 

301 

71 

307*4 

403 

99 

331-3 

298 

72 

308-4 

398 

100 

332-0 

295 

73 

309*3 

393 

110 

339-2 

271 

74 

310-3 

388 

120 

345-8 

251 

75 

311-2 

383 

130 

352-1 

233 

76 

312-2 

379 

140 

357-9 

218 

77 

313-1 

374 

150 

363-4 

205 

78 

314-0 

370 

160 

368-7 

193 

79 

314-9 

366 

170 

373-6 

183 

80 

315-8 

362 

180 

378-4 

174 

81 

316*7 

358 

190 

382-9 

166 

82 

317-6 

354 

200 

387-3 

158 

83 

318*4 

350 

210 

391-5 

151 

84 

319-3 

346 

220 

395-5 

145 

















76 


/ 


THE ENGINEER’S HANDY-BOOK. 




Explanation of the following Table. 

The first column gives the absolute pressure of the steam in 
inches of mercury, or the height to which the pressure would raise 
a column of mercury in a tube, provided the opposing pressure 
of the atmosphere were removed. 

The second column gives the absolute pressure in pounds per 
square inch under the same circumstances. 

The third column, it will be observed, is headed “Pressure 
above Atmosphere.” By this is meant the apparent pressure of 
the steam as indicated by a steam-gauge. 

The fourth column shows the temperature in degrees of Fah¬ 
renheit’s scale. 

The fifth column shows the increase of volume which the water 
assumes in the act of changing into steam. 

The sixth column shows the velocity with which steam, at the 
given pressures, escapes through an orifice into the atmosphere, as, 
for example, through the safety-valve of a steam-boiler. 


TABLE 

i 

OF THE ELASTIC FORCE, TEMPERATURE, AND VOLUME OF STEAM FROM A 
TEMPERATURE OF 32 ° TO 457 ° FAH., AND FROM A PRESSURE OF 0‘2 TO 
900 INCHES OF MERCURY. 


ELASTIC FORCE IN 

Pressure 

above 

Atmosphere. 

Temper¬ 

ature. 

Volume. 

Velocity of 
Escape. 

Inches of 
Mercury. 

Pounds per 
Square Inch. 

•200 

•098 


32 ° 

187407 


•221 

*108 


35 

170267 


*263 

•129 


40 

144529 


•316 

•155 


45 

121483 


•375 

*184 

’ ** r 

50 

103350 


•443 

•217 


55 

88388 


•524 

*257 


60 

75421 


•616 

•302 


65 

64762 


•721 

•353 


70 

55862 


•851 

•417 


75 

47771 


1*000 

•490 


80 

41031 
















THE ENGINEER^ HANDY-ROOK 


77 


TABLE 

OF THE ELASTIC FORCE, TEMPERATURE, AND VOLUME OF STEAM FROM A 
TEMPERATURE OF 32 ° TO 457 ° FAH., AND FROM A PRESSURE OF 0'2 TO 
900 INCHES OF MERCURY. 


ELASTIC FORCE IN 

Pressure 

above 

Atmosphere. 

Temper¬ 

ature. 

V 

Volume. 

Velocity of 
Escape. 

Inches of 
Mercury. 

Pounds per 
Square Inch. 

1*17 

•573 


85 -° 

35393 

i 

1-36 

*666 


90 * 

30425 


1*58 

•774 


95 - 

26686 


1-86 

•911 


100 - 

22873 


2*04 

1-000 


103 * 

20958 


2*18 

1-068 


105 - 

19693 


2*53 

1-24 


110 * 

16667 


2*92 

1-431 


115 - 

14942 


3-33 

1-632 


120 - 

13215 


3*79 

1-857 


125 - 

11723 


4-34 

2-129 


130 - 

10328 


5-00 

2-45 


135 - 

9036 


5*74 

2*813 


140 - 

7938 


6-53 

3-100 


145 - 

7040 


7*42 

3*636 


150 - 

6243 


8*40 

4116 


155 - 

5559 


9*46 

4-635 


160 * 

4976 


10*68 

5-23 


165 * 

4443 


12-13 

5-94 


170 - 

3943 


13*62 

6-67 


175 - 

3538 


1515 

7*42 


180 * 

3208 


17-00 

8*33 


185 * 

2879 


19-00 

9-31 


190 - 

2595 


21*22 

10*40 


195 * 

2342 


23-64 

11-58 


200 - 

2118 


26-13 

12-80 


205 - 

1932 


28-84 

14-13 


210 - 

1763 


29-41 

14-41 


211 - 

1730 


30-00 

14*70 

0 ‘ 

212 - 

1700 


30*60 

15-00 


212*8 

1669 


31.62 

15-50 

0*8 

214-5 

1618 


32*64 

16-00 

1*3 

216-3 

1573 


33-66 

16*50 


218 - 

1530 


34-68 

17-00 

2*3 

219-6 

1488 


35-70 

17-50 


221-2 

1440 


36*72 

18'00 

3*3 

222*7 

1411 


37'74 

18-50 


224-2 

1377 

874 

38-76 

19-00 

4*3 

225-6 

1343 



7 * 
























78 


THE ENGINEER’S HANDY-BOOK. 




TABLE 



OF THE ELASTIC FORCE, TEMPERATURE, AND VOLUME OF STEAM FROM A 
TEMPERATURE OF 32 ° TO 457 ° FAH.. AND FROM A PRESSURE OF 0*2 TO 
900 INCHES OF MERCURY. 


ELASTIC 

FORCE IN 

Pressure 

above 

Atmosphere. 

Temper¬ 

ature. 

Volume. 

Velocity of 
Escape. 

Inches of 
Mercury. 

Pounds per 
Square Inch., 

39*78 

19*50 


227 * 1 ° 

1312 


40*80 

20*00 

5*3 

228*5 

1281 


41*82 

20*50 


229*9 

1253 


42*84 

21*00 

6*3 

231*2 

1225 


43*86 

21*50 


232*5 

1199 


44*88 

22*00 

7*3 

233*8 

1174 

1135 

45*90 

22*50 


235*1 

1150 


46*92 

23*00 

8*3 

236*3 

1127 


47*94 

23*50 


237*5 

1105 


48*96 

24*00 

9*3 

238*7 

1084 


49*98 

24*50 


239*9 

1064 


51*00 

25*00 

10*3 

241 * 

1044 


53*04 

26*00 

11-3 

243*3 

1007 

1295 

55*08 

27 * 

12*3 

245*5 

973 


57*12 

28 * 

13*3 

247*6 

941 


59*16 

29 * 

14*3 

249*6 

911 

1407 

61*20 

30 * 

15*3 

251*6 

883 


63*24 

31 * 

16*3 

253*6 

857 


65*28 

32 * 

17*3 

255*5 

833 


67*32 

33 * 

18-3 

257*3 

810 

1491 

69*36 

34 * 

19*3 

259*1 

788 


71*40 

35 * 

20*3 

260*9 

767 


73*44 

36 * 

21*3 

262*6 

748 


75*48 

37 * 

22*3 

264*3 

729 

1550 

77*52 

38 * 

23-3 

265*9 

712 


79*56 

39 * 

24-3 

267*5 

695 


81*60 

40 * 

25*3 

269*1 

679 

1600 

83*64 

41 * 

26*3 

270*6 

664 


85*68 

42 * 

27*3 

272*1 

649 


87*72 

43 * 

28-3 

273*6 

635 


89*76 

44 * 

29*3 

275 * 

622 

1652 

91*80 

45 * 

30*3 

276*4 

610 


93*84 

46 * 

31*3 

277*8 

598 


95*88 

47 * 

32*3 

279*2 

586 


97*92 

48 * 

33*3 

280*5 

p- *■» 

OiO 

1690 

99*96 

49 * 

34*3 

281*9 

564 


102*00 

50 * 

35*3 

283*2 

554 


104*04 

51 * 

36*3 

284*4 

544 

1720 















79 


THE ENGINEER^ HANDY-BOOK. 


TABLE 

OF THE ELASTIC FORCE, TEMPERATURE, AND VOLUME OF STEAM FROM A 
TEMPERATURE OF 32 ° TO 457 ° FAH., AND FROM A PRESSURE OF 0 2 TO 
900 INCHES OF MERCURY. 


ELASTIC FORCE IN 

Pressure 

above 

Atmosphere. 

Temper¬ 

ature. 

Volume. 

Velocity of 
Escape. 

Inches of 
Mercury. 

Pounds per 
Square Inch. 

106*08 

52 - 

37*3 

285 * 7 ° 

534 


108-12 

53 - 

38-3 

286-9 

525 


110-16 

54 - 

39-3 

288-1 

516 


112-20 

55 * 

40*3 

289-3 

508 

1750 

114-24 

56 - 

41-3 

290*5 

500 


116-28 

57 - 

42*3 

291-7 

492 


118-32 

58 - 

43-3 

292-9 

484 

1774 

120-36 

59 - 

44*3 

294-2 

477 


122-40 

60 * 

45*3 

295-6 

470 


124-44 

61 - 

46*3 

296-9 

463 


126-48 

62 * 

47*3 

298-1 

456 


128-52 

63 * 

48*3 

299-2 

449 


130-66 

64 - 

49*3 

300-3 

443 


132-60 

65 * 

50-3 

301-3 

437 


134-64 

66 - 

51*3 

302-4 

431 

1816 

136-68 

67 * 

52-3 

303-4 

425 


138-72 

68 - 

53*3 

304*4 

419 


140-76 

69 * 

54*3 

305-4 

414 


142-80 

70 - 

55*3 

306-4 

408 


144-84 

71 - 

56-3 

307*4 

403 


146-88 

72 - 

57*3 

308-4 

398 


148-92 

73 * 

58*3 

309*3 

393 

1850 

150*96 

74 * 

59*3 

310'3 

388 


153*02 

75 * 

60-3 

311-2 

383 


155-06 

76 * 

61*3 

312-2 

379 


157*10 

77 * 

62*3 

313-1 

374 


159-14 

78 * 

63*3 

314 - 

370 


161-18 

79 * 

64*3 

314-9 

366 


163-22 

80 - 

05*3 

315-8 

362 


165-26 

81 * 

60*3 

316*7 

358 


167*30 

82 * 

67*3 

317-7 

354 


169*34 

83 - 

68*3 

318-4 

350 


171-38 

84 * 

69*3 

319*3 

346 


173-42 

85 - 

70-3 

320-1 

342 


183-62 

90 - 

75*3 

324-3 

325 

1904 

193-82 

95 * 

80*3 

328-2 

310 


203-99 

100 - 

85*3 

332 - 

295 


214-19 

105 - 

90*3 

335-8 

282 

1950 





























80 


THE ENGINEER’S HANDY-BOOK 


TABLE 

OF THE ELASTIC FORCE, TEMPERATURE, AND VOLUME OF STEAM FROM A 
TEMPERATURE OF 32 ° TO 457 ° FAIL, AND FROM A PRESSURE OF 0*2 TO 
900 INCHES OF MERCURY. 


ELASTIC 

FORCE IN 

Pressure 

above 

Atmosphere. 

Temper¬ 

ature. 

Volume . 

Velocity of 
Escape . 

Inches of 
Mercury. 

Pounds per 
Square Inch. 

224*39 

110 * 

95*3 

339 * 2 ° 

271 


234*59 

115 * 

100*3 

342*7 

259 


244*79 

120 * 

105*3 

345*8 

251 

1980 

254*99 

125 * 

110*3 

349*1 

240 


265*19 

130 * 

115*3 

352*1 

233 


275*39 

135 * 

120*3 

355 * 

224 

2006 

285*59 

140 * 

125*3 

357*9 

218 


295*79 

145 * 

130*3 

360*6 

210 


306 * 

150 * 

135*3 

363*4 

205 

2029 

316*19 

155 * 

140*3 

366 * 

198 


326*29 

160 * 

145*3 

368*7 

193 


336*59 

165 * 

150*3 

371*1 

187 


346*79 

170 * 

155*3 

373*6 

183 


357 * 

175 * 

160*3 

376 * 

178 


367*2 

180 * 

165*3 

378*4 

174 


377*1 

185 * 

170*3 

380*6 

169 

2074 

387*6 

190 * 

175*3 

382*9 

166 


397*8 

195 * 

180*3 

384*1 

161 


408 * 

200 * 

185*3 

387*3 

158 


448*8 

220 * 

205*3 

392 * 


2109 

524*28 

257 * 

242*3 

406 * 


2136 

599*76 

294 * 

279*3 

418 * 


2159 

848*68 

367 * 

352*3 

429 * 


2196 

889*64 

441 * 

426*3 

457 * 


2226 


It will be observed that in the foregoing and following tables 
the relative volume and weight of steam differs with different 
authors, and, while they may not all be scientifically correct, 
they are undoubtedly approximately so, or sufficiently correct 
for all practical purposes. Therefore, it would be perfectly safe 
to take the volume of steam at 1728; in other words, a cubic 
inch of water converted into steam at atmospheric pressure will 
occupy 1728 cubic inches, or one cubic foot. 
















81 


THE ENGINEER S II ANDY-BOOK. 


TABLE 

SHOWING THE TEMPERATURE AND WEIGHT OF STEAM AT DIFFERENT 
PRESSURES FROM 1 POUND PER SQUARE INCH TO 300 POUNDS, AND 
THE QUANTITY OF STEAM PRODUCED FROM 1 CUBIC INCH OF WATER, 
ACCORDING TO PRESSURE. 


Total Pressure 
per Square Inch 
measured from 
a Vacuum. 

Pressure 
above At¬ 
mosphere. 

Sensible 
Temperature 
in Fahren¬ 
heit degrees. 

Total Heat in 
Degrees from 
Zero of Fah¬ 
renheit. 

Weight, of 
one Cubic 
Foot of 
Steam. 

Relative Volume 
of Steam com¬ 
pared with Water 
from which it 
was raised. 

1 


102*1 

1144-5 

•0030 

20582 

2 


120-3 

1151-7 

•0058 

10721 

3 


141-0 

1150-0 

•0085 

7322 

4 


153-1 

1100-1 

•0112 

5583 

5 


102-3 

1102-9 

•0138 

4527 

0 


170-2 

1105-3 

•0103 

3813 

7 


170-9 

1107-3 

•0189 

3298 

8 


182-9 

1109-2 

•0214 

2909 

9 


188-3 

11708 

•0239 

2604 

10 


193'3 

1172-3 

•0204 

2358 

11 


197‘8 

1173-7 

-0289 

2157 

12 


202-0 

1175*0 

•0314 

1980 

13 


205-9 

1170-2 

•0338 

1842 

14 


209*0 

1177-3 

•0362 

1720 

14*7 

0 

212-0 

1178-1 

•0380 

1042 

15 

'3 

213*1 

1178-4 

•0387 

1010 

10 

1*3 

210-3 

1179-4 

•0411 

1515 

17 

2-3 

219-0 

1180-3 

•0435 

1431 

18 

3*3 

222*4 

1181*2 

•0459 

1357 

19 

4-3 

225-3 

1182-1 

•0483 

1290 

20 

. 5*3 

228*0 

1182-9 

*0507 

1229 

21 

0*3 

230-0 

1183-7 

•0531 

1174 

22 

7*3 

233-1 

1184-5 

"0555 

1123 

23 

8*3 

235-5 

1185*2 

•0580 

1075 

24 

9-3 

237-8 

1185-9 

•0001 

1030 

25 

10-3 

240-1 

1180*0 

"0025 

990 

20 

11-3 

242-3 

1187*3 

•0050 

958 

27 

12*3 

244-4 

1187*8 

•0073 

920 

28 

13-3 

240-4 

1188-4 

•0090 

895 

29 

14-3 

248-4 

1189-1 

•0719 

800 

30 

15*3 

250-4 

1189*8 

•0743 

838 

31 

10-3 

252*2 

1190*4 

•0700 

813 

32 

17*3 

254*1 

1190*9 

•0789 

789 

33 

18-3 

255-9 

1191-5 

•0812 

707 

34 

19-3 

257-0 

1192-0 

•0835 

740 

35 

20’3 

259-3 

1192-5 

•0858 

720 

30 

21-3 

200-9 

1193-0 

•0881 

707 

37 

22-3 

202-0 

1193-5 

•0905 

088 

38 

23*3 

204-2 

1194-0 

•0929 

071 

39 

24-3 

205-8 

1194-5 

•0952 

055 






















































82 


THE ENGINEER’S HANDY-BOOK. 


TABLE— ( Continued.) 


Total Pressure 
per Square Inch 
measured from 
a Vacuum. 

Pressure 
above At¬ 
mosphere. 

Sensible 
Temperature 
in Fahren¬ 
heit degrees. 

Total Heat in 
Degrees from 
Zero of Fah¬ 
renheit. 

Weight of 
one Cubic 
Foot of 
Steam. 

Relative Volume 
of Steam com¬ 
pared with Water 
from which it 
was raised. 

40 

25*3 

267*3 

1194*9 

*0974 

640 

41 

26-3 

268*7 

1195*4 

*0996 

625 

42 

27*3 

270*2 

1195*8 

*1020 

611 

43 

28*3 

271*6 

1196*2 

*1042 

598 

44 

29-3 

273*0 

1196*6 

*1065 

595 

45 

30*3 

274*4 

1197*1 

*1089 

572 

46 

31-3 

275*8 

1197*5 

•mi 

561 

47 

32*3 

277*1 

1197*9 

*1133 

550 

48 

33*3 

278*4 

1198*3 

*1156 

539 

49 

34-3 

279*7 

1198*7 

*1179 

529 

50 

35-3 

281*0 

1199*1 

*1202 

518 

51 

36*3 

282*3 

1199*5 

*1224 

509 

52 

37*3 

283*5 

1199*9 

*1246 

500 

53 

38-3 

284*7 

1200*3 

*1269 

491 

54 

39*3 

285*9 

1200*6 

*1291 

482 

55 

40-3 

287*1 

1201*0 

*1314 

474 

56 

41*3 

288*2 

1201*3 

*1336 

466 

57 

42*3 

289*3 

1201*7 

*1364 

458 

58 

43-3 

290*4 

1202*0 

*1380 

451 

' 59 

44-3 

291*6 

1202*4 

*1403 

444 

60 

45*3 

292*7 

1202*7 

*1425 

437 

61 

46*3 

293*8 

1203*1 

*1447 

430 

62 

47’3 

294*8 

1203*4 

*1469 

424 

63 

48*3 

295*9 

1203*7 

*1493 

417 

64 

49*3 

296*9 

1204*0 

*1516 

411 

65 

50'3 

298*0 

1204*3 

*1538 

405 

66 

51*3 

299*0 

1204*6 

*1560 

399 

67 

52-3 

300*0 

1204*9 

*1583 

393 

68 

53*3 

300*9 

1205*2 

*1605 

388 

69 

54*3 

301*9 

1205*5 

*1627 

383 

70 

55*3 

302*9 

1205*8 

*1648 

378 

71 

56*3 

303*9 

1206*1 

*1670 

373 

72 

57*3 

304*8 

1206*3 

*1692 

368 

73 

58-3 

305*7 

1206*6 

*1714 

363 

74 

59-3 

306*6 

1206*9 

*1736 

359 

75 

60-3 

307*5 

1207*2 

*1759 

353 

76 

61*3 

308*4 

1207*4 

*1782 

349 

t i 

62-3 

309*3 

1207*7 

*1804 

345 

78 

63-3 

310*2 

1208*0 

*1826 

341 

79 

64-3 

311*1 

1208*3 

*1848 

337 

80 

65-3 

312*0 

1208*5 

*1869 

333 

81 

66*3 

312*8 

1208*8 

*1891 

329 

82 

67*3 

313*6 

1209*1 

*1913 

325 

83 

68-3 

314*5 

1209*4 

*1935 

321 







































83 


THE ENGINEER’S HANDY-BOOK. 


TABLE — ( Continued.) 


Total Pressure 
per Square Inch 
measured from 
a Vacuum. 

Pressure 
above At¬ 
mosphere. 

Sensible 
Temperature 
in Fahren¬ 
heit degrees. 

Total Heat in 
Degrees from 
Zero of Fah¬ 
renheit. 

Weight of 
one Cubic 
Foot of 
Steam. 

Iielative Volume 
of Steam com¬ 
pared with Water 
from which it 
was raised. 

84 

69*3 

315*3 

1209-6 

•1957 

318 

85 

70*3 

316*1 

1209-9 

•1980 

314 

86 

71-3 

316*9 

1210-1 

•2002 

311 

87 

72*3 

317-8 

1210-4 

•2024 

308 

88 

73*3 

318*6 

1210-6 

•2014 

305 

89 

74-3 

319*4 

1210*9 

•2067 

301 

90 

753 

320*2 

1211-1 

•2089 

298 

91 

76'3 

321*0 

121 T 3 

•2111 

295 

92 

77'3 

321*7 

1211*5 

•2133 

292 

93 

78-3 

322-5 

1211*8 

•2155 

289 

94 

79-3 

323*3 

1212-0 

•2176 

286 

95 

80-3 

324-1 

1212-3 

•2198 

283 

96 

8 T 3 

324-8 

1212-5 

•2219 

281 

97 

82*3 

325-6 

1212-8 

"2241 

278 

98 

83-3 

326-3 

1213-0 

•2263 

275 

99 

84-3 

327-1 

1213*2 

•2285 

272 

100 

85*3 

327-9 

1213-4 

•2307 

270 

101 

86‘3 

328*5 

1213-6 

•2329 

267 

102 

87-3 

329-1 

1213-8 

•2351 

265 

103 • 

88-3 

329-9 

1214-0 

•2373 

262 

104 

89-3 

330*6 

1214-2 

•2393 

260 

105 

90-3 

331-3 

1214*4 

•2414 

257 

106 

9 L 3 

331-9 

1214-6 

•2435 

255 

107 

92*3 

332-6 

1214-8 

•2456 

253 

108 

' 93-3 

333’3 

1215-0 

•2477 

251 

109 

94*3 

334-0 

1215-3 

•2499 

249 

110 

95-3 

334-6 

1215-5 

•2521 

247 

111 

96-3 

335-3 

1215-7 

•2543 

245 

112 

97-3 

336-0 

1215-9 

•2564 

243 

113 

98*3 

336-7 

1216-1 

•2586 

241 

114 

99*3 

337-4 

1216-3 

•2607 

239 

115 

100*3 

338-0 

1216*5 

•2628 

237 

116 

101*3 

338-6 

1216*7 

•2649 

235 

117 

102*3 

339-3 

1216-9 

•2674 

233 

118 

103*3 

339'9 

1217*1 

•2696 

231 

119 

104*3 

340*5 

1217-3 

*2738 

229 

120 

105*3 

341-1 

1217-4 

*2759 

227 

121 

106*3 

34 T 8 

1217-6 

•2780 

225 

122 

107*3 

342*4 

1217-8 

•2801 

224 

123 

108*3 

343-0 

1218-0 

•2822 

222 

124 

109*3 

343-6 

1218-2 

•2845 

221 

125 

110*3 

344-2 

12184 

•2867 

219 

126 

111*3 

344-8 

1218-6 

•2889 

217 

127 

112*3 

345-4 

1218-8 

*2911 

215 





























84 


THE ENGINEER’S HANDY-BOOK 


TABLE — (Concluded.) 


Total Pressure 
per Square Inch 
measured from 
a Vacuum. 

Pressure 
above At¬ 
mosphere. 

Sensible 
Temperature 
in Fahren¬ 
heit degrees. 

Total Heat in 
Degrees from 
Zero of Fah¬ 
renheit. 

Weight of 
one Cubic 
Foot of 
Steam. 

Relative Volume 
of Steam com¬ 
pared with Water 
from which it 
was raised. 

128 

113-3 

346-0 

1218*9 

•2933 

214 

129 

114-3 

346-6 

1219-1 

•2955 

212 

130 

115-3 

347-2 

1219-3 

•2977 

211 

131 

116*3 

347-8 

1219-5 

•2999 

209 

132 

117-3 

348-3 

1219-6 

•3020 

208 

133 

118-3 

348-9 

1219-8 

•3040 

£06 

134 

119-3 

349-5 

1220-0 

•3060 

205 

135 

120-3 

350'1 

1220-2 

•3080 

203 

136 

121-3 

350-6 

1220-3 

•3101 

202 

137 

122-3 

351-2 

1220-5 

•3121 

200 

138 

123-3 

351-8 

1220*7 

•3142 

199 

139 

124*3 

352*4 

1220-9 

•3162 

198 

140 

125-3 

352-9 

1221-0 

*3184 

197 

141 

126-3 

353-5 

1221-2 

•3206 

195 

142 

127-3 

35 L 0 

1221-4 

•3228 

194 

143 

128-3 

354-5 

1221-6 

*3258 

193 

141 

129-3 

355*0 

1221*7 

•3273 

192 

145 

130-3 

355*6 

1221-9 

•3294 

190 

146 

131-3 

356-1 

1222-0 

•3315 

189 

147 

132-3 

356*7 

1222-2 

*3336 

188 

148 

133-3 

357-2 

1222*3 

•3357 

187 

149 

134-3 

357*8 

1222-5 

•3377 

186 

150 

135-3 

358-3 

1222-7 

•3397 

184 

155 

140-3 

361-0 

1223-5 

•3500 

179 

160 

145-3 

363-4 

1224*2 

•3607 

174 

165 

150-3 

366-0 

1224-9 

•3714 

169 

170 

155-3 

368-2 

1225-7 

•3821 

164 

175 

160-3 

370-8 

1226-4 

*3928 

159 

180 

165-3 

372-9 

1227-1 

*4035 

155 

185 

170-3 

375-3 

1227-8 

•4142 

151 

190 

175-3 

377-5 

1228-5 

*4250 

148 

195 

180-3 

379-7 

1229*2 

•4357 

144 

200 

185-3 

381-7 

1229-8 

•4464 

141 

210 

195-3 

386-0 

1231-1 

•4668 

135 

220 

205-3 

389*9 

1232*8 

•4872 

129 

230 

215-3 

393*8 

1233*5 

*5072 

123 

240 

225-3 

397-5 

1234-6 

*5270 

119 

250 

235*3 

401-1 

1235-7 

•5471 

114 

260 

245-3 

404-5 

1236-8 

•5670 

110 

270 

255-3 

407-9 

1237-8 

•5871 

106 

280 

265-3 

411-2 

1238-8 

•6070 

102 

290 

275*3 

414-4 

1239*8 

•6268 

99 

300 

285-3 

417-5 

1240*7 

•6469 

96 































THE ENGINEER’S HANDY -BOOK. 85 

TABLE 

SHOWING THE STEAM PRESSURE IN POUNDS PER GAUGE ; THE ABSOLUTE 
PRESSURE IN POUNDS AND INCHES OF MERCURY ; THE TEMPERATURE; 
THE TOTAL HEAT IN STEAM PER POUND ; THE LATENT HEAT PER POUND ; 
THE HEAT OF THE WATER; THE RELATIVE VOLUME, AND WEIGHT OF 
STEAM PER CUBIC FOOT, FOR VARIOUS PRESSURES.* 


Pressure 

per 

Gauge. 

Total 

lbs. 

Inches of 
Mercury. 

Temper¬ 

ature, 

Fah. 

Total Heat 
per lb. 

Latent 
Heat 
per lb. 

Heat in 
Water 
per lb. 

Relative 

Volume. 

Weight 

per 

Cub. Ft. 


1 

2 036 

102- 

1145 05 

104296 

102-08 

17983- 

•00347 


2 

4-072 

12627 

1152-45 

102601 

126-44 

10353- 

•00602 


3 

6-108 

14162 

115713 

1015-25 

14P87 

7283-8 

•00856 


4 

8-144 

15307 

116262 

1007-23 

153-39 

5608-4 

01112 


5 

10-180 

162-33 

116345 

100073 

162-72 

45656 

•01366 


6 

12-216 

170-12 

1165-83 

995-25 

170-57 

3851 0 

■01619 


7 

14-252 

17691 

1167-89 

990 47 

17742 

3330-8 

•01837 


8 

16-288 

182-91 

116972 

986-24 

183-48 

2935-1 

•02125 


9 

18324 

188-32 

117137 

982-43 

188-94 

26241 

•02377 


10 

20-360 

19324 

1172-87 

978-96 

193-92 

2373 0 

•02628 


11 

22-396 

197-77 

1174-26 

975-76 

198-49 

21663 

•02880 


12 

24432 

201-96 

117553 

972-80 

202-74 

19930 

•03130 


13 

26-468 

205-88 

1176-73 

97002 

206-71 

1845-7 

•03380 


14 

28-504 

209-56 

1177-85 

96743 

21043 

1718-9 

•03629 

•304 

15 

30 540 

213 02 

1178-91 

964 97 

21394 

1608-6 

•03878 

1-304 

16 

32-576 

21630 

117991 

962-66 

217-25 

1511-7 

•04123 

2-304 

17 

34612 

219-41 

1180-86 

960-45 

220-41 

1426-2 

•04374 

3304 

18 

36*648 

222-38 

1181-76 

958-34 

223-42 

1349-8 

•04622 

4-304 

19 

38-684 

225-20 

1182-63 

956-34 

226-28 

1281T 

•04868 

5-304 

20 

40-720 

227-92 

118345 

954-41 

229 04 

1219-7 

•05119 

6-304 

21 

42756 

230 51 

1184-25 

952-57 

23T67 

1163-8 

•05360 

7-304 

22 

44 792 

23302 

1185-01 

950-79 

234 22 

1112-9 

"05605 

8-304 

23 

46-828 

23543 

1185-74 

949-07 

236-67 

1066-3 

•05851 

9-304 

24 

48864 

237-75 

1186-45 

947-42 

239-03 

1023-6 

•06095 

10304 

•25 

50-900 

240-00 

1187-14 

945-82 

241-31 

984-23 

•06338 

11-304 

26 

52-936 

242-17 

1187-80 

944-28 

243-52 

947-86 

•06582 

12-304 

27 

54-972 

24428 

1188-44 

942-77 

245-67 

914-14 

•06824 

13304 

28 

57-008 

246 33 

118907 

941-32 

24775 

882-80 

•07067 

14 304 

29 

59-044 

248 31 

1189-67 

939-90 

249-77 

853 60 

•07308 

15304 

30 

61-080 

25024 

1190-26 

938-92 

251-74 

826-32 

•07550 

16304 

31 

63116 

252-12 

1190-83 

937-19 

253-64 

800-79 

•07791 

17304 

32 

65-152 

253 95 

1191-40 

935-88 

255-52 

766-83 

■08031 

18-304 

33 

67-188 

25573 

119P94 

934-61 

257 33 

754 31 

•08271 

19 304 

34 

69224 

25746 

1192-47 

933-36 

259-11 

733-09 

•08510 

20 304 

35 

71260 

25917 

119299 

932-15 

260-84 

713-08 

•08749 

21304 

36 

73-296 

260-83 

1193-49 

930-96 

262-53 

694 17 

•08987 

22-304 

37 

75-331 

262-46 

1193-99 

929-81 

26418 

676-27 

•09225 

23304 

38 

77-367 

264 04 

1194-47 

928-67 

265-80 

659-31 

•09462 

24 304 

39 

79403 

265-60 

1194-94 

927-56 

267-38 

643-21 

■09700 

25 304 

40 

81-439 

267-12 

1195-41 

92647 

268-94 

627-91 

•09936 

26-304 

41 

83*475 

26861 

1195-86 

925-40 

270-46 

613-34 

•10172 

27-304 

42 

85"511 

270-07 

1196 31 

924-36 

27195 

59946 

•10407 

28 304 

43 

87-547 

27P51 

1196-75 

92333 

273-42 

586 23 

•10642 

29 304 

44 

89-583 

272-91 

1197-18 

922-32 

274-86 

573-58 

•10877 

30 304 

45 

91-619 

27429 

119760 

921 33 

276-27 

561-50 

•11111 

31304 

46 

93655 

27565 

1198-01 

92036 

277 65 

549-94 

•11344 

» 32 304 

47 

95-691 

27699 

1198-42 

919-40 

279-02 

538-87 

•11577 

33-304 

48 

97-727 

278-30 

1198-82 

918-47 

280-35 

528-25 

•11810 

34-304 

49 

99763 

27958 

1199-21 

917-54 

28T67 

518-07 

•12042 

35304 

50 

101-799 

280-85 

119960 

91663 

282-97 

508-29 

•12273 


* John W. Hill. 


8 





































86 


THE ENGINEER’S HANDY-BOOK, 






TABLE 

SHOWING THE STEAM PRESSURE IN POUNDS PER GAUGE; THE ABSOLUTE 
PRESSURE IN POUNDS AND INCHES OF MERCURY; THE TEMPERATURE; 
TIIETOTAL HEAT IN STEAM PER POUND; THE LATENT HEAT PER POUND; 
THE HEAT OF THE WATER; THE RELATIVE VOLUME, AND WEIGHT OF 
STEAM PER CUBIC FOOT, FOR VARIOUS PRESSURES. 


Pressure 

per 

Gauge. 

Total 

lbs. 

Inches of 
Mercury 

Temper¬ 

ature, 

Fah. 

Total Heat 
per lb. 

Latent 
Heat 
per lb. 

Heat in 
Water 
per lb. 

Relative 

Volume. 

Weight 

per 

Cub. Ft. 

36-304 

51 

103 84 

282-10 

1198-98 

915-74 

284-24 

498-89 

•12505 

37 304 

52 

105-87 

283-32 

1200 35 

914-86 

285-50 

489-85 

•12736 

38-304 

53 

107-91 

284-53 

1200-72 

91399 

286-73 

481-15 

•12966 

39-304 

54 

109-94 

285'72 

1201-08 

913-13 

287-95 

47277 

•13196 

40304 

55 

111 98 

286-89 

1201-44 

91229 

289-15 

464-69 

•13428 

41-304 

56 

11402 

288-05- 

1201-80 

911-46 

290-34 

456-90 

•13652 

42304 

57 

11605 

289-11 

1202-14 

91064 

29P50 

449-38 

•13883 

43 304 

58 

118-09 

290-32 

1202-49 

909-83 

29265 

442-12 

•14111 

44-304 

59 

120-12 

29142 

1202-82 

909-03 

29379 

435-10 

•14338 

45304 

60 

12216 

29252 

1203-16 

908-25 

29491 

428-32 

•14566 

46304 

61 

124-19 

293-60 

1203-49 

907-47 

29602 

42P75 

•14792 

47-304 

62 

12623 

294 66 

1203-81 

906 70 

297-11 

415-40 

•15018 

48304 

63 

128 27 

295-71 

1204-13 

905-95 

298-18 

409-25 

•15244 

49304 

64 

13030 

296-75 

1204-45 

905-20 

299-25 

40329 

•15469 

50-304 

65 

13234 

297-78 

1204-76 

904-46 

300-30 

397-51 

•15694 

51-304 

66 

134-37 

298-79 

1205-07 

903 73 

301-34 

39190 

•15919 

52-304 

67 

13641 

29979 

1205-38 

90301 

302-37 

386-47 

•16130 

53-304 

68 

138-45 

300-77 

1205-68 

902 30 

303-38 

381-18 

•16366 

54304 

69 

140-48 

301-75 

1205-97 

90P60 

304-37 

37606 

•16590 

55-304 

70 

142-52 

302-72 

1206-27 

900 90 

305"37 

37107 

•16812 

56-304 

71 

144-55 

303-67 

1206 56 

900-21 

306-35 

36624 

•17035 

57 304 

72 

146-59 

304-62 

1206-85 

899-53 

307-32 

361-53 

•17256 

58-304 

73 

148-63 

305"55 

1207 13 

898-85 

308-28 

35695 

•17478 

59304 

74 

150 66 

306-47 

1207-42 

89819 

309*23 

352-49 

•17690 

60-304 

75 

15270 

30739 

1207-69 

897-53 

310-16 

348-15 

•17919 

61-304 

76 

154 73 

30829 

120797 

896-88 

31P09 

34393 

•18139 

62304 

77 

156-77 

309-18 

1208-24 

896-23 

31201 

339 81 

•18359 

63-304 

78 

158-81 

310-07 

1208-51 

895-59 

31292 

335 81 

•18578 

64301 

79 

160 84 

310-94 

1208-78 

894-95 

31382 

33P89 

•18797 

65-304 

80 

162-88 

31181 

1209-04 

89433 

314 71 

328-08 

•19015 

66-304 

81 

164 91 

31267 

1209 30 

893-71 

315-59 

32437 

•19233 

67301 

82 

166-95 

31352 

1209-56 

893-09 

316-47 

320-74 

•19451 

(58-304 

83 

168-99 

314-36 

1209-82 

892-49 

31733 

31720 

•19668 

69-304 

84 

17102 

31519 

121007 

891-88 

318-19 

31374 

•19885 

70304 

85 

17306 

316-02 

1210-33 

891-29 

31904 

310-36 

•20101 

71-304 

86 

175-09 

31684 

1210-58 

890-69 

319-89 

307 07 

•20317 

72304 

87 

17713 

317-65 

1210-83 

89011 

320-72 

30385 

•20532 

73 304 

88 

179-17 

31845 

1211-07 

889-52 

321-54 

300-70 

•20747 

74-304 

89 

18U20 

319-25 

121131 

88895 

32236 

297-62 

•20962 

75-304 

90 

185-24 

32004 

121155 

888-38 

323 17 

294-61 

•21185 

76-304 

91 

185-27 

320-82 

1211-79 

887-81 

323-98 

29166 

•21390 

77-304 

92 

187-31 

321-58 

1212-03 

887-25 

324-78 

288-78 

•21603 

78-304 

93 

189 35 

32236 

1212-26 

886-69 

325*57 

285-96 

■21816 

79-304 

94 

19P38 

323-13 

121249 

886-13 

326-36 

283-21 

•22029 

80-304 

95 

19342 

323-88 

1212-72 

885 59 

327-13 

280-50 

•22241 

81-304 

96 

19545 

324-63 

121295 

885-04 

327-91 

277-86 

•22453 

82-304 

97 

197-49 

325-38 

1213-18 

884-50 

32868 

275-27 

•22675 

83-304 

98 

199-53 

326-11 

121340 

883-97 

329-43 

27273 

•22873 

81-304 

99 

20P56 

326-84 

1213-63 

883 44 

330-19 

270-24 

•23085 

85-304 

100 

203-60 

327-57 

1213-85 

882-91 

330-94 

267-80 

•23296 



























87 


THE ENGINEER’S HANDY-BOOK. 


TABLE 

SHOWING THE STEAM PRESSURE IN POUNDS PER GAUGE ; THE ABSOLUTE 
PRESSURE IN POUNDS AND INCHES OF MERCURY; THE TEMPERATURE | 
THE TOTAL HEAT IN STEAM PER POUND ; THE LATENT HEAT PER POUND ; 
THE HEAT OF THE WATER; THE RELATIVE VOLUME AND WEIGHT OF 
STEAM PER CUBIC FOOT, FOR VARIOUS PRESSURES. 


Pressure 

per 

Gauge. 

Total 

lbs. 

Inches of 
Mercury. 

Temper¬ 

ature, 

Fall. 

Total Heat 
per lb. 

Latent 
Heat 
per lb. 

Heat in 
Water 
per lb. 

Relative 

Volume. 

Weight 

per 

Cub. Ft. 

86-304 

101 

205-64 

328-29 

121407 

882-39 

331-68 

265-81 

•23505 

87-304 

102 

207-67 

329-00 

1214-28 

881-87 

332-41 

263-07 

•23715 

88-304 

103 

209-71 

329 71 

1214-50 

881-35 

333-15 

260-77 

-23924 

89-304 

104 

211-74 

33042 

121471 

880 85 

333-86 

258-52 

•24132 

90-304 

105 

21378 

33111 

1214-93 

880-34 

334 59 

25631 

•24340 

91304 

106 

215-82 

331-80 

1215-14 

879'84 

335-30 

254-14 

*24548 

92304 

107 

21785 

33249 

1215-35 

879-34 

336-01 

25201 

•24756 

93-304 

108 

21989 

33317 

1215-55 

878-84 

33671 

249-92 

•24963 

94-301 

109 

221 92 

333 85 

1215-76 

87835 

337-41 

247 87 

•25169 

95-301 

110 

223 96 

33452 

1215-97 

877-86 

338-11 

245-86 

•25375 

96-304 

111 

225-99 

33519 

1216-17 

877-38 

338*79 

24388 

•25581 

97304 

112 

22803 

335 85 

1216-38 

87690 

339 48 

24194 

•25786 

98-304 

113 

23007 

33651 

1216-58 

876 42 

340T6 

240-03 

•25991 

99-304 

114 

23210 

337 16 

1216-77 

87594 

340-83 

238-15 

•26204 

100-304 

145 

23414 

33781 

1216-97 

875'47 

341-50 

236-31 

•26400 

101-304 

116 

236-17 

338-46 

121717 

875-00 

342-17 

234-50 

•26611 1 

102-304 

117 

238-21 

339 10 

121736 

874-54 

312-83 

232-70 

•26816 

103-304 

118 

24025 

33973 

1217-56 

874-07 

343 49 

231-00 

*27020 

104-304 

119 

242-28 

340 37 

121775 

87361 

344 14 

22930 

•27224 

105-304 

120 . 

244 32 

340-99 

1217-94 

873T5 

344 79 

227-56 

•27421 

106-304 

121 

246-35 

341-62 

121813 

872-70 

345-43 

226-00 

•27628 

107-304 

122 

248-39 

34224 

121832 

872-25 

346-07 

224-40 

•27828 

108-304 

123 

25043 

342-85 

1218-51 

871-80 

34671 

222-80 

•28027 

109304 

124 

252-46 

34346 

1218 69 

871-35 

347-34 

22120 

•28227 

110-304 

125 

254 50 

34407 

1218-88 

870-91 

347-97 

219-50 

•28422 

111-304 

126 

25654 

34468 

1219-07 

870-47 

348 60 

218-20 

-28625 | 

112-304 

127 

258"57 

34528 

1219-25 

870-03 

34922 

21670 

•28824 

113-304 

128 

260-61 

345-87 

121943 

869-60 

349 83 

215-20 

•29023 i 

114-304 

129 

262 64 

34646 

1219-61 

869-16 

350 45 

21370 

•29222 | 

115-304 

130 

264-68 

347-06 

1219-79 

868 74 

35U06 

212-07 

•29419 

116 304 

131 

266-72 

34764 

121997 

868-31 

351-66 

21090 

-29618 

117-304 

132 

268 75 

348 23 

1220 15 

867-88 

352*27 

20950 

•29816 

118-304 

133 

27079 

348-80 

1220-32 

867"46 

352-86 

208-1') 

•30013 

119-304 

134 

272-82 

349-38 

1220-50 

86704 

35346 

206-70 

•30209 

120-304 

135 

274-86 

349-95 

1220-67 

866-62 

354-05 

20518 

•30406 

121-304 

136 

276-89 

350-52 

1220-85 

866-21 

354-64 

204 10 

-10601 

122-304 

137 

278-93 

35109 

122102 

865-79 

355-23 

202-80 

•30796 

123304 

138 

280-96 

351-75 

1221-19 

865-38 

,355 31 

201-50 

•30990 

124-304 

139 

283-00 

352-21 

122U36 

864-97 

356-39 

200-20 

•31186 

125-304 

140 

285-04 

352 76 

1221-53 

864"56 

356-97 

198-78 

*31385 

126-304 

141 

287-07 

353 32 

122U70 

864-16 

357-54 

197-80 

•31586 

127304 

142 

289-11 

353 87 

1221-87 

863-76 

358-11 

19660 

"31788 

r>S'304 

143 

291-15 

35442 

1222-04 

863-36 

358-67 

19540 

•31990 

129 304 

144 

293-18 

354-96 

12-22 20 

862 96 

359*24 

194-20 

’32190 

130-304 

145 

295-22 

355"50 

1222-37 

862-57 

359-80 

192-83 

*32354 

131-304 

146 

297-25 

356 04 

1222-53 

862-17 

360-36 

191-90 

•32592 

132-304 

147 

299-29 

356"57 

1222-69 

861-78 

360-91 

190-80 

•32794 

133304 

148 

30133 

357T0 

1222-85 

861-39 

36146 

189-70 

•32995 

134-304 

149 

303 36 

357*63 

1223-02 

861-01 

362-01 

188-60 

•33196 

135-304 

150 

305-40 

358-16 

1223 18 

860-62 

362 56 

187“26 

•33315 

































The Brown Automatic Cut-Off* Steam-Engine. 

The cuts on pages 89, 90, represent the Brown Automatic 
Cut-off High-pressure Engine.—The housing, which, as will be 
observed, is of the girder-frame pattern, somewhat resembles the 
Corliss, though the engine is different in every other respect. The 
cylinder, which contains the steam- and exhaust-ports, is encased 
in an ornamental cast-iron jacket, and rests on a square, tapering 
column which extends nearly the full length. By a judicious dis¬ 
tribution of the materials, every part possesses sufficient rigidity, 
without extra weight of metal. In its design, the evils induced by 
expansion, and the liability to get out of line, have been scientifi¬ 
cally considered and practically obviated. A spur-gear on the 
main shaft gives motion to a shaft parallel with and below the 
axis of the cylinder. From this shaft the motions of the valves 
are derived. 

There are four valves, one steam and one exhaust at each end 
of the cylinder, which are independent, and though slide-valves, as 
they have but one function to perform for each revolution, i. e., 
admitting or exhausting the steam, they are necessarily of a dif¬ 
ferent construction from the ordinary slide-valve. The exhaust- 
valves are horizontal, and travel at right angles with the cylinder; 
the motion being derived from cams on the longitudinal shaft, 
which is positive in both directions. The shape of the camways 
is such that the motions of the valves in opening and closing are 
very quick, and allow of their remaining stationary during nearly 
the whole stroke of the piston, thus insuring a perfectly free ex¬ 
haust, and preventing any possibility of back pressure. 

The steam-valves, which are vertical, are of the gridiron pat¬ 
tern, and require very little movement to give a full port opening. 
They are operated by eccentrics on the cam-shaft, in connection 
with the following device for regulating the point of cut-off. A 
vibrating lifter, having the fixed centre at its outer end, is con¬ 
nected, at about the middle of its length, with the eccentric-rod; 
while the inner end engages a spring-catch or projection on the 


THE ENGINEER’S HANDY-BOOK 


89 



8 * 
























































































































90 


I HE ENGINEER’S HANDY- BO OIv 










































































THE ENGINEER’S HANDY-BOOK. 


91 


valve-stem, giving to the valve a positive motion on the left or up 
stroke, and allowing of its being tripped, or released for closing, 
when the point of cut-off is reached—jar being prevented by 
means of small dash-pots. On the spring-catch of the valve- 
stems is an inverted wedge, by means of which the valves are 
tripped. 

The governor, which, as will be observed, is enclosed in an or¬ 
namental case or shell, is very sensitive and admirably adapted to 
these engines, is of the centrifugal fly-ball type, receives a positive 
motion from the cam-shaft, by means of bevel-gears, and causes a 
rod running parallel with the shaft and back of the valve-stems 
to oscillate. On this rod and opposite to each wedge is an arm, 
which, when the speed increases, is moved by the governor towards 
the wedge, thus drawing the catch away from the lifter as it rises, 
and allowing the valve to drop, while the lifter continues its mov- 
ment to the end of the stroke and return, when it engages the 
catch as before. 

Both steam- and exhaust-valves have ample openings, which, in 
connection with their quick motions, entirely obviate the evil aris¬ 
ing from wire-drawing the steam, or choking the exhaust, thereby 
causing back pressure. The only unbalanced pressure on the 
valve is an area of about one square inch on the top, for the pur¬ 
pose of aiding in closing them quickly. As an evidence of the 
small amount of friction induced in the working of the valves of 
these machines, the ordinary starting-bar is dispensed with, and an 
eight-inch hand-wheel on the cam-shaft, which possesses sufficient 
leverage to work the valve by hand, substituted in its place. 

The valve-gear is a most ingenious and admirable combination 
of mechanical devices, being very simple, and susceptible of easy, 
convenient, and accurate adjustment. Its operation may be ex¬ 
plained as follows: The shaft, A, receives its motion from a gear 
on the main shaft, which, in turn, imparts motion to the gov¬ 
ernor, and through the medium of the frictional device, or coup¬ 
ling C , to the shaft B , on which the eccentrics, D, are located, 
the ends of the straps of which are connected to the horizontal 


92 


THE ENGINEER’S HANDY- BOOK. 


arms, E, which extend into the square slot provided in the slide- 
spindle, and to the catch of the tongue. As the shaft, B, revolves, 
the ends of the arms, E, will reciprocate vertically in the square 
slot, the valve-stem being attached to the guide, F, in the slot of 
which the tongue, G, is pivoted by the pin shown in the guide. 
The upper end of this tongue has a projecting catch upon it, be¬ 
neath which stands the end of the arm, E, which lifts the valve for 
the admission of the steam, and holds it open until the tongue is 
tripped, when the valve closes, the movement being instantaneous, 
and rendered noiseless by means of an air-cushion dash-pot. 

The governor-spindle is attached to the end of an arm which is 
fast upon a rod, which, being immediately back of the shaft B, is 
not seen in the cut; upon this rod, and immediately behind the 
steam-valve spindle-guide, F, is an arm standing vertically, and 
carrying the horizontal pin, H. The tongue which at one end 
acts as a catch to the eccentric arm, at the other end protrudes 
from the back of the slide-spindle guide, and stands directly be¬ 
neath the pin, H, so that w T heu the arm, E, lifts (through the 
tongue-catch) the steam-valve, the latter remains open until the 
tail of the catch, G, meets with the pin, H, which trips the tongue 
and closes the valve. The governor controls the position of the 
pin, H , and determines the point of cut-off. The discs, J, on the 
shaft, B, are provided with cam-grooves, into which a friction- 
roller on the rocker-arm, K, extends, the upper arm, L, being at¬ 
tached to the exhaust-valve spindle. To compensate for the cir¬ 
cular motion of the arm and the vertical movement of the valve- 
spindle, the connection between them is made by the eye of the 
spindle, containing a slot in which is fitted a sliding die, to which 
the pin of the arm is fitted. Any change of load on the engine 
is instantaneously shown by the governor. Nevertheless, the 
valve-gear is complicated, and liable to wear out rapidly and 
become a source of annoyance and expense. 


Front View of the Harris Corliss Engin 


THE engineer’s HANDY-BOOK 


93 





















































































































































































THE ENGINEER S HANDY-BOOK 







i 
1 if, 


:/ III 

: II lulfwi 

iiiii 



HHIIH3I wmll 


11 

fe/' 

i II Ml 


Back View of the Harris Corliss Engine. 







































































































































































95 


THE ENGINEER’S HANDY-BOOK. 

The Harris Corliss Steam-Engine. 

The cuts on pages 93 and 94 represent the Harris Corliss En¬ 
gine, one showing the crank and cross-head, the other the eccentric 
and vaive gear. It will be observed that the general design is 
symmetrical and well proportioned, rigidity and strength being 
introduced principally where the greatest longitudinal strain oc¬ 
curs, viz., between the cylinder-flange and the centre of the fly¬ 
wheel shaft. Between these points the frame, which is in one 
casting, is vertically deep and strongly ribbed, thus insuring 
greater strength and stiffness than could be obtained by any other 
distribution of the same amount of material. The cross-head 
guides are cast with the frame. The main pillow-block is of an 
improved design, with the feet well spread out; and the cylinder 
and exhaust-chest rest upon supports the entire width of the 
chest. The engines are only slightly elevated above the floor, 
thus allowing the attendant to reach every part with the greatest 
ease. The cylinders and chests are neatly lagged in black walnut, 
or other wood. 

The piston-packing is of the most improved kind, and is claimed 
to remain perfectly steam-tight under all circumstances. It is 
set out by means of German silver spiral springs, which obviate 
the difficulty arising from the cylinder becoming worn larger at 
the ends, or its liability to become cut or fluted, in consequence 
of its being set out too tight. Besides, the piston-rod is retained 
exactly in the centre of the cylinder. The spring plates for the 
packing-rings are made of bronze metal, consequently they are 
not liable to corrode. The distance used for the packing-ring be¬ 
tween the piston and the follower is so small that it leaves a large 
amount of the junk-ring for a bearing, or a wearing surface on the 
lower side of the cylinder in the horizontal engine, which reduces 
the liability to cut. The design and arrangement of this pack¬ 
ing afford the most convenient facilities for taking it out, putting 
it in, or for adjustment. The operation of the packing is as fol¬ 
lows: When steam is admitted into either end of the cylinder, tlie 


96 


THE ENGINEER’S HANDY-IiOOK. 


packing-ring is carried by the steam over to the side of the groove 
in the junk-ring, making a joint there, and allowing the steam to 
pass down and under the packing-ring, thus placing it in equili¬ 
brium; then all that is required is a very light spring to hold the 
packing in contact with the cylinder. 

There are four valves — two steam and two exhaust. The steam- 
valves are located on the top of the cylinder at each end, and 
open directly into the clearance, which obviates the waste induced 
by the use of long passages. The exhaust-valves are placed in 
the exhaust-chest on the lower side of tire cylinder, and, as in the 
case of the steam-valves, open into the clearance spaces, which ar¬ 
rangement facilitates the escape of the water of condensation from 
the cylinder, and obviates the liability to accident. The four 
valves are moved by one eccentric through the intervention of a 
wrist-plate; the same valves admit and cut off the steam. 

The steam-valve in these engines commences to open its port at 
one end of the cylinder when the eccentric is producing its most 
rapid movement, and, as the motion of the eccentric is declining 
towards the end of the throw, an increasing speed is obtained by 
means of the wrist-plate, which compensates for the slow motion 
of the eccentric. At the same time the steam-valve at the oppo¬ 
site end of the cylinder commences to lap its port by the motion 
of the eccentric, but by a reverse or subtraction of speed pro¬ 
duced by the same wrist-plate, which speed is constantly decreas¬ 
ing till the throw of the eccentric is completed. Or in other 
words, the lapping and opening of the steam-ports require each the 
same amount of throw of the eccentric, producing, for instance, a 
lap of 2 an inch at one end of the cylinder, while the opposite 
end has an opening of one inch and one-eighth. The exhaust- 
valves are moved by the same eccentric and the same wrist-plate 
before spoken of, but they have a much greater travel for the 
purpose of ridding the engine of the exhaust steam easily through 
the exhaust-ports, which are as Tong and twice as wide as the 
steam-ports, and therefore back pressure on the piston of the en¬ 
gine is avoided. The rapid opening and slow lapping of the ex- 


THE ENGINEER’S HANDY-BOOK. 


97 


haust-ports are obtained in the same manner as in the case of the 
steam-ports, but much faster, as the travel is greater on the open¬ 
ing of the exhaust than on the opening of the steam-port, in order 
to get a free and full opening. 

The variations of load upon these engines are communicated 
to the steam-valves instantly by the governor, the valves being 
moved by a force distinct from it, yet subjected to its regulation, 
lhe governor in no case performs any work, and only indicates 
the changes required to the levers which move the valves, and 
needs only sufficient force to move a small stop. Its movement 
is attended with the least possible friction; the stop presents 
hardly any resistance to the governor, except at the very instant 
when it is in actual contact with the lever constituting its fulcrum. 
This momentary resistance by the bearing of the lever on the 
stop as a fulcrum occupies so small a space of time that, com¬ 
pared with the period during which the governor is left free to 
move the stop, it is practically nothing. As a precautionary 
measure, a safety stop is connected with the valve-gear, so that in 
case the governor should become inoperative, and should fail to 
act, the steam-valves become unhooked, and cannot open, and, as 
a universal result, the engine is stopped, although the valve in the 
steam-pipe may be wide open. The valves are circular, and oscil¬ 
late on fixed bearings in the front and back bonnets. The valve- 
stems have flat blades, which extend the whole length of the valves 
in the steam-chest, and to which levers are keyed for the purpose 
of giving them motion. The valves are fitted in such a manner 
as to be capable of adjusting themselves to their seats, as their 
faces and seats become warm. Any one of them can be adjusted 
independent of the other, and can be removed from the valve- 
chests by unscrewing four bolts, and withdrawing a key at the 
point at which it is attached to the lever. The valve-gear of 
these engines may be worked by hand, even under extreme steam 
pressure. 

The valve-stems of these engines are packed with an improved 
metallic packing, which is claimed to possess many advantages in 
9 G 


98 


THE ENGINEER’S HANDY-BOOK. 


respect to freedom from friction and wear, over hemp, cotton, or 
any other fibrous substance, for the stems of oscillating or vibrat¬ 
ing engines, ns illustrated by the following cut: 


f ; n 

i / 



Fig. 1. 


A represents the valve, B the valve-seat, and D the valve-stem 
or rod, which is outside the chest, and upon the end of which is 
the toe with which the valve-gear engages to rock the valve to 
enable the port to be opened. E is a standard or bracket pro¬ 
jecting from the side of the steam-chest, and bolted thereto, 
through which the valve-rod passes, and by which the valve-rod, 
and the valve connected with it, are sustained and supported in 
their proper relation, all of which is familiar to the construction 
of steam-engines. At the inner end of the bracket, E, and con¬ 
centric with the hole through which the valve-rod passes, a recess 
is cut. A collar, E, is then shrunk upon the valve-rod, or other¬ 
wise tightly fitted thereto, so as to make a flange, and is turned 
off to face and fit the recess when the valve-rod,valve, and bracket 
are in their proper relation. The face of the flange, E } and the 
seat of the recess, a, should also be round, so as to make a steam- 
tight joint. 

The Harris Corliss Engines possess no advantages over other 
automatic cut-off engines; in fact, they are said to be inferior in 
many respects to some engines of the same type. 
























THE ENGINEER’S HANDY-BOOK. 


99 


Questions 

FOR ENGINEERS, THE ANSWERS TO WHICH WILL BE FOUND UNDER 

THE HEADS OF THE RESPECTIVE SUBJECTS TO WHICH THEY RE¬ 
LATE. A PROMPT ANSWER WILL SHOW THAT THE CANDIDATE 

HAS STUDIED THE SUBJECT, AND IS MASTER OF THE SITUATION, 

AND VICE VERSA. 

What are the best aids to candidates applying for an engineer’s 
certificate or license? 

What qualifications, both mental and physical, ought candi¬ 
dates applying for a Cadetship in the United States Navy to pos¬ 
sess? 

What qualifications should candidates for the position of en¬ 
gineers and assistant engineers in the United States Revenue ser¬ 
vice possess? 

What are the necessary qualifications of applicants for the 
positions of engineers and assistant engineers in the Mercantile 
Marine service? 

What qualifications are necessary for persons taking charge 
of stationary engines in any locality requiring a license? 

Give the names of the different triangles. 

What is steam? 

What 1 aw does the expansive property of steam follow? 

What is surcharged steam? 

Will it affect the vacuum? 

What is saturated steam? 

> 

What is supersaturated steam? 


100 


THE ENGINEER’S HANDY-BOOK. 


To what are the temperature and the elastic force of steam 
equal? 

What is the difference in the pressure of steam when the mer¬ 
cury is in a vacuum, or when exposed to the atmosphere? 

If the proper relation of the temperature between the steam 
and the water from which it is formed be disturbed, what will be 
the effect? 

What is the total heat of steam at 212° Fall.? 

How is the latent heat of steam found? 

\ 

When does heat in steam become latent? 

How would you ascertain what amount of water is necessary to 
condense a given quantity of steam? 

What is low-pressure steam? 

Why is the steam of salt water fresh? 

What is the most extraordinary property of steam? 

What are the two modes of applying the power of steam to the 
cylinders of steam-engines? 

State the rule for finding the mean or average pressure in a 
cylinder. 

Is the effluent velocity with which steam of different pressures 
flows into the atmosphere uniform? 

State the difference between the latent and sensible heat of 
steam at different pressures. 

State the total heat and relative volume of steam at different 

> > ) 

pressures. 


101 


THE ENGINEER’S IIANDY-BOOK. 

As the sensible heat in steam increases, does the latent heat 
decrease? 

In what way does the change affect the economy of the steam- 

engine ? 

What is meant by the volume of steam? 

What is the difference in volume between water and steam at 
atmospheric pressure? 

How much does one cubic foot of steam at atmospheric press¬ 
ure weigh? 

State the velocity with which steam at different pressures flows 
into the atmosphere or into steam of a lower pressure. 

If steam, at a given pressure, be cut off in the cylinder at a 
certain point of the stroke, what will be the pressure for the whole 
length of the stroke? 

Give the rule for finding the amount of benefit to be derived 
from working steam expansively. 

Give the rule for finding the average pressure of the steam in 
the cylinder for different points of cut-off. 

Is surcharged steam indicated by the steam-gauge? Or will it 
affect the vacuum ? 

What is superheated steam? 

What is the steam-jacket? 

What is the difference in effect between superheated and sat¬ 
urated steam ? 

Which is capable of producing the most economical results? 

9* 


102 


THE ENGINEER’S HANDY-BOOK. 


PART SECOND. 


Steam-Engines in General. 

Steam-engines embrace a great variety of designs and names; 
such as the beam, side-lever, inclined, oscillating, trunk, horizontal, 
vertical, and steeple, which are in turn termed single-acting, double¬ 
acting, reciprocating, rotary, semi-rotary, compound duplex, in¬ 
verted, and geared, each of which was probably designed to meet 
some peculiar requirement — either economy of space, fuel, or ef¬ 
ficiency in speed. (Judging from the appearance of things at 
present, the horizontal and vertical are destined to supersede all 
other designs for land and marine purposes.) 

All steam-engines, of whatever design, or for whatever pur¬ 
pose employed, are embraced under two heads, commonly called 
high- and low-pressure, but more properly termed condensing and 
non-condensing. In the non-condensing engine, the steam, after 
acting on the piston, escapes into the open air; therefore the 
pressure of the outgoing steam must exceed atmospheric pressure, 
or 14*7 lbs. to the square inch. Thus, if steam at 45 lbs. average 
pressure above vacuum be admitted to the piston of a high-press¬ 
ure engine, it will exert a force equal to its pressure; but 14*7 
lbs. per square inch of that pressure will not be converted into 
work, as it will be lost in overcoming the pressure of the atmos¬ 
phere, which may be illustrated by the following example: 

Diameter of cylinder, 12 in.; area, 113*09 in. 

Average steam pressure per square inch, 45 lbs. 

Total steam pressure, 5089*05 lbs. 

As before, area, 113*09 sq. in. 

Atmospheric pressure, 14*7 lbs. 

Total atmospheric pressure, 1662*423 lbs. 

5089*050 

f 

Loss due to atmospheric pressure, 1662*423 

Effective steam pressure on piston, 3426*627 lbs. 




THE ENGINEER’S HANDY-BOOK. 103 

The foregoing example shows the resistance to be overcome at 
each stroke of the piston before the steam acting against it can 
produce any useful effect. Thus it will be seen that the piston 
of a high-pressure steam-engine is exposed to the action of two 
pressures, namely, the pressure of the steam from the boiler on 
one side, and that due to the atmosphere and the steam remaining 
in the cylinder after exhaust takes place on the other. The 
pressure utilized or converted into work will be the difference 
between the two. 

In the low-pressure or condensing engine, the steam, after 
acting against the piston, escapes into a condenser, where it is 
condensed into water and a vacuum is formed ; thus rendering not 
only a considerable portion of the steam pressure in the boiler, 
but also the 147 lbs. per square inch required in the non-con¬ 
densing engine to overcome the pressure of the air, available as an 
effective force against the piston, which may be explained as follows: 

Diameter of cylinder, 12 in.; area, 113*09 sq. in. 

Average steam pressure per square inch, 45 lbs. 

Total effective steam pressure, 5089*05 lbs. 

As before, area, 113*09 sq. in. 

Vacuum at best, 13 lbs. 

Power due to vacuum, 1470*17 lbs. 

3958*15 

147077 

Total effective pressure due to steam and vacuum, 5428*32 lbs. 

The back pressure in the condenser, which represents the differ¬ 
ence between the indications of the vacuum-gauge and a perfect 
vacuum,must be deducted; but, as a perfect vacuum is not attain¬ 
able, the back pressure varies from 2 to 5 lbs., according to the 
condition of the engine and the quantity of uncondensed steam 
remaining in the condenser. 

Waste in the high-pressure engine. — In the best types of 
modern high-pressure engines, the useful effect obtained from the 
work stored up in good fuel may be calculated as follows: 



104 


THE ENGINEER’S II ANDY-BOOK. 


Loss through bad firing and incomplete combustion, 10 per cent. 

Carried off by draught through chimney, 30 “ “ 

Carried away in the exhaust steam, 50 “ “ 

Utilized in motive power (indicated), 10 “ “ 

100 per cent. 

The foregoing may seem incredible, and yet any one wishing 
to do so may demonstrate its truthfulness to his own satisfaction 
by placing a thermometer in the steam-pipe and noting its tem¬ 
perature during its escape from the boiler to the cylinder; then 
placing it in the exhaust-pipe, close to the engine, and noting the 
temperature at this point, when it will be discovered that the 
steam has lost very little of its heat in passing through the cyl¬ 
inder. Consequently the difference in temperature between the 
steam when it escapes from the boiler and from the exhaust-pipe, 
constitutes all of the heat that was contained in the fuel that was 
utilized. 

Waste in the low-pressure or condensing engine. —According 
to the dynamic theory of heat, as shown on page 105, a certain 
weight of coal contains within itself a certain amount of work 
stored up, and ready to rush out under the necessary surround¬ 
ings, as in the case of a compressed spring set free. The supply 
of a given weight of coal to the furnace of a steam-boiler repre¬ 
sents the application of a definite amount of force at one end of 
a series of transformations, a part of which force at length 
appears as useful work at the other, the balance having been 
wasted in the various processes through which it has passed. 

Take, for example, a modern marine-engine of the best con¬ 
struction and design. The force supplied to the furnace in the 
combustible is first developed as heat by the burniug of the coal; 
a portion of this heat is utilized in changing the water into 
steam, the balance being wasted either in radiation, or by being 
carried off in the hot gases through the chimney. A part of the 
steam formed is applied to move the piston, the remainder being 
wasted by condensation against the sides of the pipes and cylin- 



THE ENGINEER^ HANDY-BOOK. 105 

ders, and by leakage past the piston or valves into the con¬ 
denser. 

It is thus shown that only a small portion of the total force 

contained in the steam that is applied to move the piston is util¬ 
ized. Of the force that is utilized in the cylinder, only a small 
portion performs any external work, the remainder being absorbed 
in overcoming the back pressure induced by the friction of the 
machine itself. Of the remaining small portion that may be ap¬ 
plied to the screw, another part is wasted in overcoming its use¬ 
less resistances, and only the balance used to propel the ship. 




PER CENT. 

Total heat in one hundred lbs. of antlira- 



cite coal, in units of heat. 

1,400,000 


Deduct heat equivalent to weight of 



aslies.*. 

200,000 


Total heat in one hundred lbs. of an- 



thracite coal. 

1,200,000 

100 

Carried off by hot gases in chimney... 

200,000 

16§ 

Available to produce steam. 

1,000,000 

83i 

Lost by leakage and condensation. 

200,000 

161 

Available to perform work in cylinder. 

800,000 

66f 

Escaped with steam into condenser. 

660,000 

55 

Transformed into work. 

140,000 

lit 

Absorbed in overcoming resistance of 



engine and load. 

40,000 

H 

Available to turn the propeller. 

100,000 

81 

Absorbed in useless resistance of the 



screw..... 

20,000 

11 

Usefully applied to propel the ship. 

80,000 

61 


The following figures represent approximately the supposed 



























10G THE ENGINEER’S HANDY-BOOK. 

distribution of the total force in the best engines. No estimate is 
taken in them of the coal that is consumed in various ways on 
board ship other than those mentioned, as, for instance, in getting 
up steam, or in steam used to work pumps, in steam lost through 
the safety-valves, in heat lost in blowing off, or remaining in the 
furnaces after the vessel has arrived in port. These and other 
causes usually add at least ten per cent, to the consumption, 
leaving the force utilized about six per cent, of the total force ex¬ 
pended in the coal. The cost of an indicated horse-power, by the 
figures, would be 2} lbs. of coal per hour nearly. 

To mitigate as far as possible the foregoing losses, the surface- 
condenser ai)d boiler arrangements should be designed so as to 
insure a rapid circulation of the water, that condition being of the 
greatest importance to produce efficiency in the heating or cooling 
surfaces. Whenever practicable, the feed-water should be used 
as injection to condense the educted steam, so that it might be 
heated to the highest possible point before being sent into the 
boiler. 

It is a question of vital importance to the owner of a steamship, 

that the consumption of fuel be reduced to the lowest possible 
amount, as each ton of fuel excludes a ton of cargo. As improve¬ 
ments in the form of the hull and machinery are effected, less 
power and less fuel will be required to propel a vessel through the 
water a given distance; but, great as have been the improvements 
effected in marine engines to this end, much yet remains to be 
accomplished, as while the consumption of fuel has been reduced, 
by working steam more expansively in vessels of later date, from 
three or four to less than two pounds per effective horse-power, 
yet, comparing this with the total amount of energy in two pounds 
of coal, it will be found that not a tenth part of the power is ob¬ 
tained which that amount of coal would theoretically call into 
action. 

To find the quantity of coal required to drive a steamship a 

given number of days in average fair weather. The beam in feet 
squared will give the quantity of coal required in net tons. But 


THE ENGINEER’S HANDY-BOOK. 


107 


it must be understood that, with equal beams, the displacement, 
and consequently the power required, vary very much ; or, in 
other words, the displacement is not always proportionate to the 
beam in vessels of the same model, nor is the power required to 
propel them always proportionate to the displacement. 

When steamships are running through still water and still air, 
the loss due to the resistance of the atmosphere is about ten per 
cent, of the whole power expended, ninety per cent, being absorbed 
in overcoming the resistance of the water. 

Economy of the condensing over the non-condensing engine.— 
When the resistance of the atmosphere is removed from the piston, 
the steam may be cut off earlier, and further expanded in the 
cylinder. This reduces the draught on the boiler, and admits of a 
slower combustion of the fuel. In this way economy is promoted 
by condensation of the exhaust steam and by the vacuum formed 
in the cylinder. A vacuum equal to 14 lbs. per square inch is 
85 per cent, saving in fuel, or the same increase in power; but 
this saving undergoes a great reduction, in consequence of the 
cylinder being open alternately to the lower temperature in the 
condenser, which varies with the degree of expansion employed, 
being least when the steam follows full stroke, which is very 
seldom the case. The practical gain, therefore, in the condensing 
engine is from 20 to 80 per cent., varying with the conditions 
above named, as shown in the working of condensing engines, 
both stationary and marine. The economy of the condensing en¬ 
gine might be increased, if advantage could be taken (as in the 
case of the injector and steam-jet) of the velocity with which the 
exhaust steam escapes from the cylinder to the condenser. On 
entering the condenser, the power due to its energy is entirely de¬ 
stroyed by the cold water injection, or by being brought in contact 
with refrigerating surfaces. 

Economy in modern steam-engines, condensing and non-con¬ 
densing. —In Watt’s time, 1 cubic foot or 62J lbs. of water was 
the allowance per horse-power per hour for average engines, but 
the water consumption for most engines was from 75 to 80 lbs.; 


108 


THE ENGINEER’S HANDY-BOOK. 


while the better class of modern automatic cut-off high-pressure 
engines will yield a horse-power from a water consumption of 
from 20 to 25 lbs., and in the best class of condensing engines of 
from 18 to 22 lbs.; but, in either case, the water consumption de¬ 
pends a good deal on the size of the engines, and the excellence 
of the design and workmanship, quality of steam, pressure, etc. 
The last condition exerts a very important influence on the quan¬ 
tity of water required to develop a horse-power. 

The mean effective pressure on the piston of a steam-engine 
is the exponent of the work performed. The term “ effective 
pressure” means the amount by which the total pressure behind 
the piston exceeds that which acts on the other side in opposition 
to its movement. The “ terminal pressure,” or that at which the 
steam releases itself from the cylinder, is the corresponding expo¬ 
nent of the consumption of water by the engine, or the cost of the 
power. Hence, the best economy is attained when the mean effec¬ 
tive pressure is highest relatively to the terminal pressure ; and 
anything that will increase the former without correspondingly 
increasing the latter, or which will diminish the latter without cor¬ 
respondingly diminishing the former, will improve the economy. 

The difference in effect between the condensing and non-con¬ 
densing engine, with equal pressure of steam and expansion, is 
solely that the condensing engine has the advantage of the effect 
produced by the vacuum, or the amount of atmospheric pressure 
removed. Their difference in operation is, that in the condensing 
engine, the steam, after having performed its duty in the cylinder, 
is condensed by the admission of a spray of cold water, or being 
brought in contact with cooling surfaces, thus producing a vacuum 
or minus pressure, which varies, according to the perfection of the 
machinery, from 10 to 13 lbs. per square in.; while in the non^on- 
densing engine, the steam, after having performed its duty, is 
discharged into the atmosphere. Thus, the advantages of the 
vacuum are lost; some of the waste heat, however, is utilized by 
leading the exhaust steam through a heater, for the purpose of 
heating the feed-water. 


THE ENGINEER^ HANDY-BOOK. 


109 


Compound Engines. 

A compound engine is a high- and low-pressure condensing 
engine, with two cylinders and pistons. The steam is first ad¬ 
mitted to the small or high-pressure cylinder, until the piston has 
moved through a certain distance, when the valve is so regulated, 
that the communication with the boiler is cut off, the remainder 
of the space to be passed through by the piston being performed 
by the expansion of the steam, which, having done its work, es¬ 
capes to the condensing cylinder, where it does a proportionate 
amount of work, and out of which it escapes into the condenser. 

With respect to the number and arrangements of the cranks 
and cylinders of compound engines, there are five or six designs 
used for screw propulsion ; but the most generally adopted is the 
inverted, vertical, direct-acting, with the cylinders both high- and 
low-pressure, placed alongside of each other in the fore and aft 
direction of the ship, and the steam-chests between them con¬ 
nected direct with the two cranks on the shaft beneath. Another 
kind is that of an inverted, direct-acting engine, with one cylinder 
placed above the other, the high-pressure being uppermost. In 
this case there is only one piston-rod, which is continued through 
both cylinders and pistons, one connecting and consequently only 
one crank, a fly-wheel being generally employed to assist the 
engine in passing over the centres. In another type, which is 
known as the Huntoon, the high-pressure cylinder is placed 
within the low-pressure. In another, known as the Smart en¬ 
gine, there are four cylinders — two high-pressure and two low ; 
the two high-pressure cylinders being placed on the tops of the 
low ones, the piston-rods passing through both cylinders and con¬ 
nected directly with the cranks. Lastly, the design most gener¬ 
ally adopted for war-vessels is the horizontal, in which the cylin¬ 
ders are placed side by side. 

It is claimed that in the better class of compound engines 2 
lbs. of coal will develop a horse-power; but the want of reliable 
data to the contrary would warran-t the assertion that 3 lbs. of 
10 


i 



Modern Marine Compound Engine. 






























































































































































































































































































the engineer's handy-book. 


Ill 



The annexed cut represents the section through the cylinders, steam-chests, 
cross-heads, pillow-blocks, etc., of a Compound Marine Engine. A, A, 
show the high-and low-pressure cylinders; B, B, the pistons; G, G, the 
piston-rods; D, D, the steam-chests; E, E, the exhaust cavities; F, F, 
valve-rod guides; 77, 77, connecting-rods; 7, 7, cranks; J, J, crank-shaft; 
77, 77, 77, pillow-blocks; L , L, foundation-plate; c, c, cross-heads; a, a, 
b, b, cross-head-guides; d, d, d, d, eccentrics. The steam is admitted from 
the boilers to the steam-chest of the high-pressure cylinder, from which 
it is exhausted into the receiver and readmitted into the low-pressure 
cylinder, after which it escapes to the condenser. 







































































































































































































































































































































































































112 


THE ENGINEER’S HANDY-BOOK. 


coal are oftener consumed in the development of a horse-power 
than 2 lbs. Taking 3 lbs. as equivalent to a horse-power per 
hour, theoretically only about one-sixteenth part has been util¬ 
ized. The advantages of compound over simple engines is an 
open and unsettled question, as it is claimed that some simple 
engines in use at the present time are more economical in the use 
of fuel than compound engines; but economy of fuel is not the 
only consideration which leads to a choice of the compound en¬ 
gine for marine service, since, perhaps, the more equal distribu¬ 
tion of the power throughout the stroke is a feature of value in 
these as in all other engines where the resistance is devoid of the 
controlling influence of the fly-wheel. The disadvantages of com¬ 
pound engines are their extreme first cost, extra weight, and com¬ 
plication of parts. 

The receiver is a chamber between the cylinders of compound 
engines into which the steam from the high-pressure cylinder es¬ 
capes, and from which it is admitted to the low-pressure cylinder. 
The receiver may be said to be the steam-drum for a low-pressure 
cylinder; its capacity might be infinite,except for the weight and 
expense it would incur. In the majority of independent com¬ 
pound engines, the capacity of the receiver is about equal to that 
of the low-pressure cylinder, though for engines in general its 
capacity is regulated by certain attending circumstances. Such 
engines as the Worthington have no receivers. 

Simple Engines. 

All steam-engines are divisible into two classes, simple and 
compound ; the latter being those in which the steam is used 
twice, by being exhausted from one cylinder into another, while 
the former applies to all engines which use steam only once, 
whether they are double engines and have double sets of valve- 
gear or not. The term single engine is sometimes used; but it 
is liable to give rise to confusion. 

Locomotives, steam fire-engines, and stationary engines which 


THE ENGINEER’S HANDY-BOOK. 


113 


take their steam directly from the boiler and exhaust it into the 
atmosphere should be termed simple engines, regardless of the 
number of cylinders. An impression very generally prevails 
among engineers that compound engines are of necessity marine 
engines, and also condensing, which is a mistake, as there are 
both high-pressure and low-pressure, or condensing and non¬ 
condensing compound engines. Condensing compound engines 
generally have not more than two cylinders, although in some 
instances they have three, while non-condensing compound en¬ 
gines are met with which have four. 

Marine Engine. —The term marine engine is in very common 
use, but it has no definite meaning, as it may be either condensing 
or non-condensing, vertical, horizontal, or inclined, simple or 
compound. The only reason that can be assigned for designating 
it a marine engine is that it was designed to be used on steam¬ 
ships. A marine engine, properly speaking, is an engine designed 
to occupy a certain space on a vessel, and be capable of developing 
a certain amount of power. The most desirable class of marine 
engines are those that develop the greatest amount of power with 
a given area of piston and steam pressure, and that occupy the 
least space. The vertical engine is more in favor with marine 
engineers, as it possesses many advantages over any other design. 
This perhaps arises from the fact that it occupies less floor space; 
that it is more compact, and less liable to spring than an engine 
of any other design; and that the weight is against the lifting- 
force of the reciprocating and revolving mechanism ; also that, in 
consequence of the housing and pillow-block bearings being in one 
piece, they are less liable to get out of line than those of any other 
arrangement; and that they afford better facilities for a direct 
connection with the propeller shaft than any other. Trunk and 
oscillating engines are still employed in England for marine pur¬ 
poses, but only on war-vessels. Such designs never were looked 
upon with much favor by enlightened engineers. 

10* H 


\ 






114 


THE ENGINEER’S HANDY-BOOK. 


w 


>—l 


W 

O 

w 

6 

Ch 

M 

P 

P 

o 


cc 


C 


Cfc 


W 

ft 


« 

P 

W 

P 

Pi 

>-t 

P 

P 

O 


u 

y 




i—( 

o 

P 

P 

W 

P 


P 

o 

P 

P 

>* 

◄ 

P 

►H 

H 

P 

O 





























































115 


THE ENGINEER’S HANDY-KOOK. 


H 

J 

fQ 

< 

E-i 


*—l 

C 

w 

I 

<£ 

£ 


P 

P 

P 


P 

o 


co 



ft 


H 

£ 

P 

P 

W 

P 

P 

w 

A 

P 

O 







O 

P 

P 

w 

p 

w 

o 

p 

p 

> 


K 


H 

P 

O 




























































116 


THE ENGINEER’S HANDY-BOOK. 


Uncertainty of Tests made for the Purpose of Comparing 
the Relative Economy of Marine Engines. 

It has been customary heretofore, in order to determine the 
relative economy of marine engines, to weigh the amount of coal 
consumed in performing a certain amount of work. So long as 
all the machines compared are of the same design and dimensions, 
the coal used of the same kind and quality, and the pressure "of 
the steam, the degree of vacuum, the rate of expansion, the tem¬ 
perature of the atmosphere, and all other circumstances are the 
same, it may be inferred that any difference in the economy is the 
result of some imperfection in the engine itself. But if there is a 
variation in one particular only, as, for instance, in the degree of 
vacuum, the difference may be assumed to be due to that varia¬ 
tion ; but if there are several variations at the same time, where 
there are different kinds of engines or boilers and different steam- 
pressures, when there is any gain or loss of economy, it is impos¬ 
sible to decide to which of the variations the change is due. So, 
also, where high pressure of steam is carried, and a greater expan¬ 
sion is employed, if a poor economy is shown, it may happen that 
the benefits that should result from the high pressure and the in¬ 
creased expansion were counteracted by the increased condensa¬ 
tion and leakage, or that the power which was gained in the 
engine was lost in the boiler, or vice versa. Then, again, any dif¬ 
ference in the kind of fuel employed, or in the skill and manage¬ 
ment, unite with the other variations to render the actual results 
more unsatisfactory. 

In attempting to compare the results of such experiments as 
are recorded to determine the most economical design of engine, 
it will be generally found that the experiments made to determine 
one certain point are not sufficiently complete to serve any other 
purpose, and have generally been made by different men, under 
different circumstances and in different localities; and, moreover, 
that the expert is almost invariably biassed by prejudice. This 
is particularly applicable to the reports which may be obtained 


117 


THE ENGINEER’S HANDY-BOOK. 

of the performances of new and improved engines, whicli may he 
accounted for in this way: A steamship company may place on 
its lines a vessel of fine model, with the most improved machinery, 
which, on comparison, would show more satisfactory results than 
one of the same capacity but of inferior lines, and propelled by 
an inferior style of engine. It will be found, on comparison, that 
the profits resulting from the new ship and improved engines are 
largely in excess of those of the old; but it would, at the same 
time, be difficult to separate the gain due to the improvement in 
the model of the hull from that due to the improved engines, and 
vice versa. All that can be done in such cases is to accept the 
whole result, without being able to separate the one from the 
other. A series of exhaustive experiments to determine the 
relative economy of different classes of steam-engines and boilers 
is very much needed, but the difficulties to be encountered are so 
numerous as to render such an undertaking impracticable. 

Power of steam-engines. —The power which a steam-engine 
can furnish is generally expressed in “ horse-power,” the “ nominal 
horse-power” being admitted to be a force capable of raising a 
weight of 33,000 pounds* one foot high in one minute, or 150 
pounds 220 feet high in the same length of time. If an engine is 
rated at 25 horse-power, it is recognized as being capable of rais¬ 
ing 33,000 pounds one foot high twenty-five times in each minute. 
The question will naturally arise, How are these 33,000 pounds to 
be raised? The answer to which would be, by belts, pulleys, cog- 
gearing, cables, paddle-wheels, screw-propellers, or whatever mechan¬ 
ical arrangement is most practicable and convenient. 

There are several terms employed to express the power of en¬ 
gines, such as the “ nominal,” “ indicated,” “ actual or net,” “ dy¬ 
namo-metrical,” and “commercial” horse-power. The indicated 
horse-power is obtained by multiplying together the mean effective 
pressure in the cylinder as shown by the diagram, the area of the 
piston in square inches, and the speed in feet per minute, and 


* Foot-pounds. 





118 


THE ENGINEER’S HANDY-BOOK. 

dividing the product by 33,000. The actual or net liorse-power 
is the total available power of an engine; it equals the indicated 
horse power less the amount expended in overcoming the friction. 
The dynamo-metrical horse-power is the net horse-power after 
allowing for friction. The term commercial horse-power is some¬ 
times used, but has no definite meaning, as there is no recognized 
rule among engineers by which to buy or sell engines. 

Estimating the power of steam-engines. — There are three con¬ 
ditions necessary to be understood, before we can calculate with 
any degree of accuracy the power which a steam-engine is capa¬ 
ble of developing— first, the number of square inches in the 
piston; second, the effective pressure exerted against each square 
inch of the same ; third, the speed of the piston in feet per minute. 
Nor can the power which a steam-engine is exerting be demon¬ 
strated by any calculation, however accurate, unless the condition 
of the engine aud the back pressure be also known, which latter 
can only be determined by the indicator. 

Howto increase the power of steam-engines. —The three most 
practical methods of increasing the power of a steam-engine are, 
1st. To enlarge the diameter of the cylinder; 2d. To increase the 
speed; 3d. To increase the pressure of the steam. But the in¬ 
crease in any case must have a very narrow limit, as, if the diam¬ 
eter of the cylinder be increased much, the other parts of the en¬ 
gine will be too light. The steam pressure cannot be increased 
more than the boiler can safely bear, nor can the speed be in¬ 
creased beyond what the revolving and reciprocating parts of the 
engine will bear. But the power of any high-pressure engine can 
be very materially increased by attaching a condenser and an air- 
pump to it, providing the water supply is sufficient. 

Speed of engines. —The speed of steam-engines is generally 
counted by strokes, one stroke being half a revolution, or one 
revolution being two strokes. The crank travels from one dead- 
centre to the other to make one stroke, the distance travelled by 
the crank-pin while making a stroke being twice the distance be¬ 
tween the centres of the crank-pin and crank shaft. To find the 


THE ENGINEER’S HANDY-BOOK. 


119 


travel of piston in feet per minute, multiply the distance travelled 
for one stroke in inches by the whole number of strokes in inches, 
and divide by 12. 

Over-stroke. —This term is used when the position of the piston 
in the cylinder is so altered by taking up the lost motion in the 
boxes that it strikes either cylinder-head when the crank is at 
the dead-centre. 

The Locomotive.* 

In estimating the power of a locomotive, the term horse-power 
is not generally used, as the difference between a stationary steam- 
engine and a locomotive is, that while the stationary engine raises 
its load, or overcomes any directly opposing resistance with an 
effect due to its capacity of cylinder, the load of a locomotive is 
drawn, and its resistance must be adapted to the simple adhesion 
of the engine, which is the measure of friction between the tires 
of the driving-wheels and the surface of the rails. 

The power of the locomotive is estimated in the moving force 
at the tread of the tires. It is called the tractive force, and is 
equivalent to the load the locomotive could raise out of a pit by 
means of a rope passed over a pulley and attached to the circum¬ 
ference of the tire of one of the driving-wheels. The adhesive 
power of a locomotive is the power of the engine derived from the 
weight on its driving-wheels, and their friction or adhesion to the 
rails. 

If the wheels of a locomotive were geared into toothed rails, 
its power would be the force with which its wheels could be made 
to turn, or the weight or force which, if applied at the rims of 
the wheels, would prevent them from turning. But if the wheels 
revolve on smooth rails and slip in turning, a part of the power 
would be wasted, and the effective power of the engine limited by 
the friction or adhesion of its driving-wheels. Hence the terms 

*For full particulars on this subject, see Roper’s “Hand-Book of the 
Locomotive.” 



120 


THE ENGINEER’S HANDY-BOOK. 


“ tractive power ” and “ adhesive power ” mean respectively the 
revolving power and the progressive power of the engine. 

The Steam Fire-Engine.* 

Steam fire-engines are simply hydraulic machines similar to 
steam-pumps, and the conditions involved in their employment 
are precisely the same. They are also steam-engines, with their 
machinery adapted to a special purpose, it being perfectly imma¬ 
terial whether they are movable or stationary. Their means of 
locomotion is only a matter of convenience. The result of the 
working of the steam fire-engine may be measured by the hydraulic 
effect, and the power utilized may be determined by the quantity 
of water delivered. 

To determine the efficiency of steam fire-engines, it is necessary 
to note— first, the extreme vertical height and horizontal distance 
to which the water can be thrown ; second, the volume or quantity 
delivered in a certain time; third, the total power consumed in 
performing that work. 

Rule for finding the horse-power of steam-engines. 

Multiply the area of the piston in inches by the average steam 
pressure in pounds per square inch; multiply this product by the 
travel of the piston in feet per miuute,f and divide this product by 
33,000; the quotient is the horse-power. 

Rule for finding the horse-power of steam fire-engines. 

Multiply the area of the piston in inches by the steam pressure 
in pounds per square inch ; multiply this product by the travel 
of the piston in feet per minute, and divide this last product by 
33,000; ‘7 of the quotient will be the liorse-power. 

Rule for finding the horse-power of a locomotive. 

Multiply the area of the piston in inches by the pressure in 

* For a full description of all the steam fire-engines in use at the present 
day, their peculiarities of design, construction, efficiency, etc., see Roper’s 
‘‘Hand-Book of Modern Steam Fire-Engines.” 

f Which should never be less than 250 feet per minute; in fact, that should 
be the minimum piston speed for all classes of engines. 




THE ENGINEER^ HANDY-BOOK. 


121 


pounds per square inch; multiply this product by the number 
of revolutions per minute; multiply this by twice the length of 
the stroke in feet or inches; multiply this last product by 2 and 
divide by 33,000; the result will be the horse-power. 

Rule for finding the liorse-power of simple condensing engines. 

Multiply the area of the piston in inches by the mean effective 
pressure in pounds per square inch ; multiply this product by the 
velocity of the piston in feet per minute ; multiply the atmos¬ 
pheric pressure in pounds per square inch on the bucket of the 
air-pump by its velocity in feet per minute; subtract the last 
product from the second, and divide the remainder by 33,000 ; the 
quotient will be the horse-power of the engine. 

In estimating the horse-power of steam-engines by the fore¬ 
going rules, not more than two-thirds of the boiler pressure should 
be taken ; as the analysis of a large number of indicator diagrams 
shows that the average pressure in the cylinders of slide-valve 
engines rarely, if ever, exceeds two-thirds of the boiler pressure. 
This difference is due to the reduction caused by the pipes, stop- 
valves, and the condensation in the pipes, cylinder, etc. 

Rule for finding the horse-power of a steam-engine by indicator 
diagrams. 

Multiply the area of the piston by its travel in feet per minute, 
and divide by 33,000; the quotient will be the value of one pound 
of mean effective pressure, which, if multiplied by the total mean 
effective pressure, as shown by the card, will give the indicated 
horse-power. 

Example. —Area of piston, 113. 

Travel of piston in feet per minute, 333J. 


1 13 X 333J 
33,000 


— 1T41 horse-power value of 1 lb. M. E. P, 
36 M. E. P. as shown by the card. 


6846 

3423 


11 


41 *076 horse-power. 





122 


THE ENGINEER’S HANDY-BOOK. 





*31 d 


■w//////////mWz 


mam 


wm/a 
, /' / .• 


*** -nX/ 






WmMmm, 

. 


WMw/M 


y$s§M 




v/M v/y/////, 


The above cut shows a section of the cylinder, piston, and 
steam-chest of an ordinary slide-valve engine; a represents the 
cylinder; b ,the piston ; c, the piston-rod; o o, recesses in the cylinder- 
head ; lc k, steam-ports; /, exhaust cavity in the valve-seat; n, exhaust 
opening in valve-face; e, valve; /, valve-rod ; d d, steam-chest; m, 
bonnet of steam-chest, and h h, clearance. 

The term clearance is understood by engineers to mean the un¬ 
occupied space between the piston- and cylinder-heads when the 
crank is at the dead-centre; but it also applies to the space be¬ 
tween the cylinder and the face of the valve or valves, either 
slide or poppet. The amount of clearance of any engine affects 
its economy; and if the clearance is small, the engine will be more 
economical than if large; a certain amount is an absolute neces¬ 
sity. It is, therefore, an object of importance, in point of economy, 
to have the valve-face as near the base of the cylinder as possible. 
In this lies one of the most important features of the Buckeye, 









































































the engineer’s handy-book. 


123 


Brown, Putnam, Woodruff and Beach, etc., and, in fact, all en¬ 
gines of the Corliss type. The clearance varies with different 
builders, and in different engines from H to 10 per cent, of the 
cubic contents of the cylinder. 

The clearance is often as high as fifteen per cent., in some old- 
fashioned long stroke, slide-valve engines. This arose from a mis¬ 
conception, at the time they were designed, of the waste the large 
clearance would occasion, and is, perhaps, in many instances, due 
to the caprice of the inventor of some patent piston, who made his 
piston-rings of less depth than the original designs, thus increasing 
the space between the piston- and cylinder-heads, when the crank 
is at the dead-centre. There are even cases to be met with, where 
the old fashioned, hemp-packed piston has been replaced by me¬ 
tallic packing of not more than half its depth, without any means 
being taken to fill up the spaces at each end of the cylinder. 
Now, providing that the clearance is fifteen per cent, of the cubic 
contents of the cylinder, and that the engine makes from one 
hundred and fifty to two hundred strokes per minute for ten 
hours, it may easily be seen how enormous the waste must be. 
The quantity of fuel that might be saved by replacing such an 
engine by one in which the clearance would be reduced to a mini¬ 
mum, would more than pay for the latter in five years. Persons 
employing steam-power, or intending to purchase steam-engines, 
should pay attention to the foregoing fact. 

As the clearance space is generally irregular in form, particu¬ 
larly in slide-valve engines, it is somewhat difficult to calculate 
the exact cubic space. The most accurate method of ascertaining 
the exact amount of the clearance is to place the crank at the 
dead-centre, and fill the space with water up to the face of the 
valve (the quantity of water being previously weighed or meas¬ 
ured). Then deduct the amount remaining in the vessel from the 
whole, and the remainder will be the quantity contained in the 
clearance in cubic inches or gallons, as the case may be. 


124 


THE ENGINEER^ HANDY-BOOK. 


The Woodruff & Beach Automatic Cut-Off High-Pressure 

Engine. 

The cut on the opposite page represents the Woodruff & Beach 
high-pressure automatic cut-off engine. Fig. 1 shows a section of 
the cylinder-valves, steam passages, and exhaust passages. Fig. 2 
is a back view of the cylinder, steam-chests, valve-gear, etc. With 
the exception of the Corliss, it is the oldest variable cut-off engine 
in the country, and one that has undergone fewer changes in its 
mechanism than any other. Those who remember it thirty years 
ago, will fail, at the present day, to discover much difference from 
its general appearance. For more than a quarter of a century it 
has successfully competed with such engines as the Corliss, and it 
has always sustained a high rating in the scale of comparative 
merit. The bed-plate, as will be observed, is of the ordinary box 
O. G. pattern, to which the cylinder-guides and pillow-blocks are 
bolted and do welled in such a manner that the possibility of their 
getting out of line is entirely obviated. 

The steam-valves, which are of the double poppet form with 
bevelled faces and seats, are located at the back of the cylinder at 
each end, horizontal with its axis. Their stems project inward, 
and, owing to the peculiar shape of the cam which gives the 
motion, the opening and closing is done very quickly and almost 
noiselessly. They have independent adjustments, so that the 
steam lead may be varied to meet auy requirement without inter¬ 
fering with the rest of the valve-gear. The power required to 
work the valves in these engines is very slight, and as the cam- 
lug and the ends of the valve-sterns are made of hardened steel, 
they show no perceptible sign of wear after years of use. 

The exhaust-valve, which is cylindrical in form and has a very 
convenient arrangement for taking up the wear and preventing 
leakage, is placed at the bottom of the cylinder, and communi¬ 
cates with it by its own ports or passages, which are entirely sepa¬ 
rate from those of the steam-valve. An equilibrium of pressure 
is maintained by the exhaust taking place through the interior 


The Woodruff & Beach Automatic Cut-Off High-Pressure Engine. 


THE ENGINEER^ HANDY-BOOK 


125 



11 * 





































































































































































































































126 


THE ENGINEER’S HANDY-BOOK. 


of the valve, and as its stroke is very short, the liability to wear 
is slight. Its motion is derived from a transverse shaft under the 
centre of the guides, carrying an eccentric, and driven by bevel- 

gears. Owing to the 
position of the ex¬ 
haust openings at 
the bottom of the 
cylinder, and their 
ample size, the ex¬ 
haust is very free; 
the discharge of any 
water that may ac¬ 
cumulate from con¬ 
densation or from 
priming in the boil¬ 
ers is rendered easy, 
and all danger of 
accident from this 
cause is obviated. 

The governor, 
which is very pow¬ 
erful and sensitive, 
and of a kind that 
is admirably adapt¬ 
ed to these engines, 
is located centrally 
between the steam- 
valves, and receives 
its motion from a 
longitudinal shaft, 
supported on bear¬ 
ings attached to the 



Fig. 1. 


bed-plate, dnd driven by a spur and bevel-gear from the crank¬ 
shaft. Its spindle passes through a compound eccentric carrying 
a movable cam-lug, which, by its rotation, gives the opening or 


































































































THE ENGINEER'S HANDY-BOOK. 


127 


outward motion to the valves, in which direction it is positive; 
while the closing, although controlled by the cam, is effected by 
the pressure of the steam upon the unbalanced area exposed at 
the outer end, and is 
assisted by a spiral 
spring. In the bore 
of the inner eccen¬ 
tric is an inclined or 
spiral slot for the re¬ 
ception of a key at¬ 
tached to the gov¬ 
ernor-spindle, from 
which the eccentric 
receives its motion. 

As the key is raised 
or lowered by the 
variations of the 
governor, the inner 
eccentric is turned 
to the right or to 
the left, and the 
cam-lug moved in 
or out, as the case 
may be, thereby 
giving the neces¬ 
sary opening to the 
valve, and cutting 
off’ the steam at the 
right point to allow 
of the proper de¬ 
gree of expansion. 

As the cam-lug is 
at all times in the 



Fig. 2. 


same relative position to the outer shell of the eccentric, the lead 
of the steam-valve is not affected by the variations. 
















































































































































128 


THE ENGINEER’S HANDY-BOOK. 


The expansion-gear of these engines is oneof the most ingenious, 
simple, and effective mechanical devices that can be employed for 
that purpose. Its operation may be explained as follows: The 
cam, marked C, Fig. 3, cuts off the steam with certainty at any 
part of the stroke, the motion being produced automatically by 
the action of the governor upon it, throwing it more or less out 
of centre with the spindle of the governor; the rotation of the 
balls being more or less rapid, the eccentricity of the cam deter¬ 
mines the amount of steam admitted to the cylinder. To produce 
this effect the cam is made of two pieces. C is a hollow shell or 



cylinder, with a part of one end formed into a cam proper. 
Throughout the whole length of this piece, upon the inside, there 
is a spiral groove cut to receive one end of a feather, by which its 
pitch or eccentricity is regulated. The inside piece, D, (Fig. 4) is 
a hub which exactly fits into the hollow of the cylinder, 0, and has 
a socket, e, into which the spindle of the governor is secured, the 
.other end, d, forming a journal or bearing with a bevel-wheel on 
its extremity, to transmit the motion from the crank-shaft gearing 
to the governor and cut-off. There is a hole throughout the length 
of the inside piece, D, which is continued through the spindle of 
the governor, and which contains the rod which connects the cam 
with the governor. This hole is eccentric to the outside surfaces 
of I) and C, but is concentric with the collar, /, and with the 
governor-rod. Both pieces, C and D, are connected by a feather, 
one piece of which is of a spiral form, and the other straight; the 
























THE ENGINEER’S HANDY-BOOK. 129 

two being connected together by a stub which fits into a hole or 
bearing in the spiral piece, so that the latter can turn on the stub 
and accommodate itself to the groove in which it works. The 
spiral part of the feather works in a spiral groove in the inside 
of the shell, C, and the rectangular piece works in a straight 
groove on the inside of the hub, I), the inner part of the rectan¬ 
gular piece being fastened to the governor-rod, so that the feather 
is permanently connected with the governor. When the several 
pieces are put together the cam is complete, as shown in Fig. 4, 
and it operates as follows: Motion is communicated by gearing 
from the crank-shaft to the bevel-wheel on the end of the piece, 



Fig. 4/ 




D, as well as to the spindle of the governor, which is screwed into 
the socket on D; as the balls rise or fall through change in the 
centrifugal force, due to the variation in the speed of rotation, 
they raise or depress the governor-rod, which passes through the 
spindle, and the piece, D, which is attached to the feather thereby 
raising or depressing it. This feather acting on the spiral groove 
instantly alters the lift of the cam, and regulates the amount of 
steam admitted to the cylinder. By these means any speed may 
be selected at which the load of the engine is to move, and any 
variation from that will be instantly felt by the governor, and cor¬ 
rected. There is no jar in the working of the parts; the feather 
moves noiselessly in its grooves; the governor-rod moves up and 
down through the spindle and the piece D , and can be regulated 
to give any required opening of the steam-ports to suit the work 
to be done. 

I 


































130 


T PI E ENGINEER’S HANDY-BOOK. 

The Woodruff &. Beach engines are very simple in design, and 
have the reputation of being very durable and economical. Ab¬ 
sence of complication in the valve-motion, and the ease with which 
all the working parts can be adjusted, are valuable features. 

Automatic Cut-Off aiul Throttling Engines. 

All steam-engines, for whatever purpose designed or em¬ 
ployed, are either automatic cut-off or throttling. In the auto¬ 
matic cut-off engines, the steam-valves are so controlled by the 
governor, as to cut off the steam at any point from zero to three- 
quarter stroke — the cut-off taking place earlier, or later, to accom¬ 
modate the varying load on the engine and the pressure in the 
boiler, the object being to obtain full boiler pressure at the com¬ 
mencement of each stroke, and maintain it to the point of cut-off, 
leaving the balance of the stroke to be completed by expansion, 
the speed of the engine being controlled by the cut-off and not by 
throttling. In engines of this class, there is no impediment (save 
such as may occur at the port of entrance) to the free flow of 
steam from the boiler to the cylinder, the regulation being effected 
not by diminishing the pressure, but by cutting off in the cylinder 
the volume of steam necessary for each particular stroke; conse¬ 
quently, the only loss in pressure between the boiler and the cyl¬ 
inder is that due to the number of bends, and the length of the 
connecting pipe. 

Although all intelligent engineers are agreed upon the superior 

economy of the automatic cut-off’engine, few, excepting those who 
have had the opportunity of making a practical comparison, are 
aware of the great saving in the expense of fuel over that class 
of engines wherein the point of cut-off is invariably relative to 
the stroke of the piston. It is well understood, that the amount 
of work realized, as compared to the total theoretical work due 
the volume of steam expended, even in the most perfect engine, is 
a very small percentage of the whole energy ; and it is, therefore, 
the more an object of interest to know precisely what the differ- 


THE ENGINEER’S HANDY-BOOK. 


131 


ence is between these two classes of engines in point of economy. 
The conditions which insure the highest grades of economy are a 
full port with no intervening obstructions to impede the free flow 
of the steam, and a rapid movement of the cut-off, or steam-valve, 
over the port; as mere increase in the mean effective pressure, re¬ 
sulting from a tardy closing of the port, represents no gain during 
one stroke of the piston that may be stored up and expended 
during the succeeding stroke ; hence, any force upon the piston in 
excess of that required to balance the resistance will result in a 
diminished economy. 

The economy of high-pressure engines is exactly in propor¬ 
tion as their average piston pressure is higher than the terminal, 
providing the latter does not fall below that of the atmosphere; 
the highest economy being attained when the stroke is commenced 
with full boiler-pressure, and the steam quickly and completely 
cut off, at a point in the stroke that allows the pressure to fall to, 
or very near, that of the atmosphere. 

Throttling Engines. 

Throttling engines are those in which the flow of steam from 
the boiler to the cylinder is regulated either by a throttle-valve, a 
kind of damper in the steam-pipe, which, as the speed of the en¬ 
gine increases, is turned, and stops off the supply of steam, or by 
the steam in its passage from the boiler to the cylinder oozing 
through the passage of some peculiar type of governor-valve. 
An engine controlled by any such device is in a condition some¬ 
what like that of a horse restrained by a brake applied to the 
wheels of a wagon. Such relics of barbarism are fast giving place 
to the automatic cut-off arrangement, by which the brakes are 
removed from the wheels, and the bit placed in the horse’s mouth, 
instead. Manufacturers of this class of engines claim that they 
give results equal to the automatic cut-off engines, which is un¬ 
true, both as to economy and close governing. With an early cut¬ 
off, which is absolutely necessary to good economy, it is simply 


132 


THE ENGINEER’S HANDY-BOOK. 

impossible to govern the speed of throttling engines closely, with 
even a moderate change in load and pressure. 

In the best types of throttling engines, in consequence of the 
peculiar construction of the governor-valve, and the tortuous pas¬ 
sage through which the steam has to travel, the pressure in the 
cylinder is in many cases not more than one-half of the boiler press¬ 
ure; the effect of which is, that when the work to be performed is 
varying in its nature, such engines increase their speed when any 
considerable load is thrown off, and decrease it when additional 
load is put on. Now, every stroke an engine makes above its 
regular speed is a waste of steam, and if the engine is large, or 
runs at a high speed, the volume of steam, and consequently of 
fuel, wasted will be enormous; likewise every stroke an engine 
makes below its ordinary speed, when work is thrown on, lessens 
production. The loss of one revolution in ten diminishes the pro¬ 
ductive capacity of every machine driven by the engine 10 per 
cent.; in short, the loss of one revolution in ten diminishes the 
productive capacity of the whole factory 10 per cent ; while the 
expense of conducting the whole business, rent, wages, insurance, 
etc., continues the same as if everything was in uniform motion. 
A variation of one revolution in ten is quite common in throttling 
engines: in fact, it is unavoidable. 


Steam-Engine Cut-Offs. 

The great desideratum in the use of steam is the most perfect 
application of the expansive principle. As the pressure of steam 
is always calculated in pounds per square inch above atmospheric 
pressure, the nearer the indicated line of expansion approaches 
that of the atmosphere, the greater is the actual power derived 
from the utilized volume of steam. Were the boiler pressure and 
the load or resistance on an engine always uniform, it would be 
an easy matter, by making the cylinder of the necessary dimen¬ 
sions, to set the cut-off at the proper point for allowing of proper 
expansion. As, however, the pressure and load are constantly 


THE ENGINEER’S HANDY-BOOK. 


133 


varying, it is necessary to reduce the consumption of steam to a 
minimum which, by its perfect expansion, will give the required 
power. To these considerations may be attributed the efforts 
which have resulted in the adoption of the three devices now in 
use, viz., the positive, adjustable, and variable, or automatic cut-offs. 

In the positive cut-off the expansion of steam is effected by what 
is known as lap on the valve, by which the steam is cut off at the 
same point in each stroke, independent of load or pressure; al¬ 
though in some instances the expansion of steam in the cylinder 
is effected by an independent cut-off riding on the back of the 
main valve, and receiving its motion from an eccentric. Such an 
arrangement, like the former, is productive of beneficial results; 
but nevertheless it is very defective, inasmuch as it is stationary, 
and cannot be varied to meet the requirements of work, pressure, 
and speed. 

In the adjustable cut-off the expansion is effected by an inde¬ 
pendent valve, which can be adjusted by the engineer, outside of 
the steam-chest, by means of a screw, hand-wheel, or other me¬ 
chanical arrangement to meet the requirements of work and 
pressure. The link, in its application to the steam-engine, belongs 
to this class of cut-offs. Although such arrangements are adjust¬ 
able, they are not self-adjusting, and when once set will cut-off* 
independent of circumstances. 

The variable or automatic cut-off performs its functions accord¬ 
ing to circumstances of load and pressure, both in admitting and 
cutting off* the steam. It gives regularity of motion and secures 
all the benefits of expansion, as the governor operates the mechan¬ 
ism which determines the exact point in the stroke where the 
supply of steam from the boiler should be cut off* and expansion 
begin. This insures the most perfect regulation under the most 
varying circumstances, as the slightest change in the position of 
the governor will increase or decrease the initial charge of steam 
admitted, thus balancing any variation in the amount of resist¬ 
ance. It must not be inferred from the foregoing that any me¬ 
chanical arrangement that may be termed by its inventor an auto- 
12 


134 tjie engineer’s handy-book. 

matic cut-off is capable of producing economical results, as many 
of them are nothing but rattle-traps, undeserving of the name of 
automatic cut-offs. 

The cut-offs most generally used on steam-boats, tugs, and fer¬ 
ries, are either the Stevens, Sickles, or Winters. They all receive 
their motion from an eccentric on the main shaft. The Stevens 
cut-off has two rock-shafts,— one for the steam and one for the ex¬ 
haust,—which are operated by two separate eccentrics. The Sickles 
cut-off is operated by an eccentric, the valves being tripped by a 
wedge, so arranged as to disengage the valve-gear at any point of 
the stroke. Dash-pots are employed to ease the valves into their 
seats. The Winters cut-off is operated by a revolving shaft, which 
receives its motion from an eccentric. One of the advantages of 
this cut-off is that it can be arranged to cut off at any desired 
point of the stroke when the engine is in motion, but neither the 
Stevens nor the Sickles can. Zachariah Allen, of Providence, 
R. I., was undoubtedly the inventor of, and the first to practically 
apply, the automatic cut-off, which is unquestionably one of the 
greatest improvements ever made in the steam-engine. 


Design of Steam-Engines. 

The design or improvement of any class of machinery must 
be based upon two suppositions, either that existing mechanism is 
imperfect in its construction, or that it lacks functions which a 
new design may supply. In most cases it would seem that any 
machine, or part thereof, is susceptible of improvement; yet it will 
be generally found no easy matter to hit upon a design, or con¬ 
ceive a plan, to remedy the existing fault. Therefore no person 
should undertake to design a machine unless he is well acquainted 
with the principles involved in working it. He should be able 
to calculate strength, strains, and forces, and apply the calcula¬ 
tions so as to apportion the quantity and form of the material in 
the various parts of the machine, in order to produce the greatest 
amount of strength with the least expenditure of material. Be- 


THE ENGINEER’S HANDY-BOOK. 135 

sides a design may be based on right principles, and yet unfore¬ 
seen mechanical difficulties may prevent its application; it may 
introduce complication of parts, incur extra expense, or not be 
susceptible of convenient or easy adjustment. The fewer the 
parts, and the more harmonious the action, the more valuable the 
machine will be, providing it embodies a good principle in its 
design. 

Before any correct formulae by which to determine the proper 
proportions for steam-engines can be deduced, there are many 
things to be considered, such as permanent load, weight of mov¬ 
ing material, nature of motion, etc. The load on the piston-rod 
consists of the piston at one end, and the cross-head at the other; 
consequently the greater the length between these two points the 
more the rod is affected. For this reason, it is obvious that, when 
it becomes necessary to determine the area of the piston-rod, the 
pressure area of cylinder load and length of travel must be duly 
considered. The connecting-rod being hung between a sliding and 
a rotary motion, the load is in some measure due to the length of 
the rod in proportion to the circle described. In the first case, the 
sliding-point has a load on it due to the weight of the piston-rod, 
beyond the stuffing-box, with the additional weight of the cross¬ 
head. In the second instance, the rotating surface is affected by 
the weight of the rod and that of the crank. 

To determine the diameter of the crank-shaft we must take 
into account the weight of the crank as a lever, and the pressure 
of steam as the weight on the end of the same. The proportions 
of the crank-pin are likewise modified according to pressure, per¬ 
manent load, length of stroke, shearing strain, etc. 

The most valuable features of a steam-engine are strength, 
durability, simplicity, fewness of parts, and easy and convenient 
arrangements for the adjustment of its working parts; as its 
economy will depend on the harmonious action of its reciprocat¬ 
ing and revolving mechanism, as well as on the nature of the 
material and the excellence of the workmanship employed in its 
construction. 


136 


THE ENGINEER’S HANDY-BOOK. 


Duplicating the Paris of Steam-Engines. 

Duplicating the parts of any class of machines is an advantage, 
as it insures more uniform proportions in their original construc¬ 
tion than could otherwise be obtained, as the term duplication 
of parts conveys the impression that they are made to standard 
gauges, and for any number of machines must retain the propor¬ 
tions of the original. While duplication of parts is convenient, 
and sometimes of great value in cases of emergency, it is rarely 
so in case of repairs ; since, as soon as any journal or bearing is 
put into use, its dimensions begin to change, the cylinder com¬ 
mences to enlarge and the piston to diminish. This change of 
sli^pe extends to the piston-rod, and glands of the stuffing-boxes, 
wrist-pins, crank-pins, rocker-shafts, etc. The eccentric wears flat 
on two sides, in consequence of the thrust at these points, and the 
straps wear flat, owing to the push and pull at two points. 

Now how can it be expected that a new eccentric will fit the 
old straps, or the new straps conform to the old eccentric, or that 
the new piston will prove a good fit for the old cylinder, or the 
new piston-rod for the worn-out gland ? If the crank-shaft be¬ 
comes worn oval, it will not adjust itself to a new main-bearing 
made from the original standard ; or if the crank-pin becomes worn 
tapering, owing to the engine being out of line, a box made of the 
original proportions will not drop into its place and work har¬ 
moniously ; but, as before stated, in case of emergency, such as 
break-downs, or where interruption to business would entail great 
loss, duplicate parts are a tolerably good make-shift, and that is 
all that can be said in their favor. For this reason, the duplica¬ 
tion of parts, which in case of breakage would be most likely to 
disable a machine, ought to be encouraged, especially in case of 
marine engines, locomotives running in sections of the country 
where there are no repair shops, and stationary engines located 
in isolated places. 


THE ENGINEER’S HANDY-BOOK. 


137 


Fitting the Cranks of Steam-Engines to their Shafts. 

Boring the hole for the shaft in the crank is not so easy a task 
as the average engineer would suppose. Theoretically, when the 
hole is bored in the crank, if the boss is faced true, and then bolted 
to a true face-plate on a lathe, it must be true. But inaccuracy 
frequently arises from the fact that there are few face-plates which 
are true, and continue to remain so for any length of time. And 
even when the boring is as well done as can be expected under 
the circumstances, the crank is frequently thrown out of line in 
keying it on the shaft. For this reason, no crank should leave 
the works where it was made without being tested after having 
been keyed on. 

When the crank is in the form of a disc, or wheel, the best 
plan is to turn it true, first on a mandril, and then so fit it to the 
shaft, and the key to its seat, that after the keying it will run 
true; but with the ordinary crank, this cannot be so easily done, 
as all the surface available for testing its truth is near the centre; 
in such cases, the main reliance must be placed in fitting the key as 
well as the crank itself to the shaft. The key should never be finally 
driven till it has first been frequently partially driven, its points 
of contact filed or scraped, and it fits perfectly its whole length. 

The essential conditions necessary for the production of a well¬ 
fitting and durable crank-shaft journal are, good material, a stiff*, 
strong lathe, a skilful machinist, and a sharp, well-tempered, and 
correctly set tool. The finishing cuts should be light, and, if it 
cannot be made sufficiently smooth with the tool, it must not be 
filed, but may be ground and polished smooth by blocks of wood, 
lead, copper, or some other suitable material fitted to the journal 
in such a manner that the imperfections left by the turning-tool 
will be corrected instead of aggravated by the use of a file or end 
of a stick, as is commonly the case. The polishing powder used 
should be very fine; emery is considered, by many, objectionable for 
polishing wearing surfaces, but on good homogeneous material, free 
from flaws, fine emery may be used without any injurious effects. 

12 * 


138 


THE ENGINEER’S II ANDY-BOOK. 


The Putnam Machine Company’s Automatic Cut-Off Engine. 

The opposite cut represents the Putnam Machine Company’s 
high-pressure variable cut-off engine, the frame or bed-plate of 
which is designed with reference to strength and rigidity, and also 
to answer either for right or left hand pillow-block bearings. The 
almost universal reciprocating valve-motion derived from an ec¬ 
centric is dispensed with, and a rotary motion derived from a gear 
on the crank-shaft substituted. By means of mitre-gears the mo¬ 
tion is communicated to a shaft running parallel with the axis of 
the cylinder beneath the valves, and carrying cams for lifting the 
latter. The steam-chests, one at either end of the cylinder, contain 
each a steam and an exhaust valve of the balance or double-poppet 
form, having flat faces and seats, and are capable of being removed 
entire from the steam-chests by simply removing a bonnet or cover 
on the top of the latter. The valve-stems pass through the neces¬ 
sary stufflng-boxes in the bottom of the steam-chests. The shape 
and adjustment of the cams for working the valves give them the 
proper lift, lap, lead, etc. The opening and closing of the valves 
are very quick, the duration of opening being an interval of rest 
between the upward and downward motions. 

The governor, which is of the ordinary centrifugal form, is 
driven by bevel-gears from the cam-shaft, thus receiving a positive 
motion. Below the cam-shaft is a rack-shaft having; three arms, 
the centre one of which is attached to the lifting-rod or spindle 
of the governor, from which the rack-shaft receives a slight oscil¬ 
lating motion, while those at the ends, which are at right angles 
with the centre arm, connect with the lifting toes of the steam- 
valve. The shape of the lower faces of the lifting toes which rest 
upon the cams is such, that when moved inward towards the cyl¬ 
inder, by the motion of the governor transmitted through the 
rack-shaft, a curved upward offset is reached by the cam as it re¬ 
volves, and the valve is lowered so quickly as to have the effect 
of being actually released and allowed to drop to its seat, while at 
the same time it is supported by the lifter. The interval between 


The Putnam Machine Company’s Automatic Cut-Off Engine. 


































140 


THE ENGINEER’S HANHY-BOOIv. 

the full lift of the valve and the reaching of the offset by the 
highest point of the cam determines the point of cut-off, and in¬ 
sures sufficient lift of the valves. The advantage claimed for this 
arrangement is, that by keeping the valve always supported while 
open, the danger of slamming is avoided without the necessity of 
a dash-pot, which, in cases where the valve is tripped or released, 
is absolutely indispensable. 

When these engines are started, and until the speed for which 
the governor is adjusted is reached, the steam necessarily follows 
full stroke, as the cut-off* is inoperative. But as soon as the reg¬ 
ular speed is attained, the motion of the governor thrusts the 
centre arm of the rack-shaft downward, thereby causing the arms 
to which the lifting toes are connected to move towards the cyl¬ 
inder. This brings the offsets of the lifting toes nearer to the 
cams, causing them to drop sooner, thus cutting off the steam at 
the proper point. In case of the removal of the entire load from 
the engine, induced by the breaking of a belt, etc., the governor, 
owing to its positive motion, will effectually check any attempt at 
“ running away,” as the offsets on the lifting toes will be thrust so 
far inward, that the cams will not raise the valves from their seats 
until the speed is again reduced to the proper point. 

It is claimed that, under the above-mentioned circumstances, the 
engine will not make one full revolution before being completely 
under the control of the governor. All the sliding and bearing 
surfaces of the valve-gear of these engines are made of hardened 
steel, thus preventing the liability of rapid wear, and also requir¬ 
ing very little power to move the valves. The fly-wheels are 
turned on the face and edges. The shafts, crank-pins, and con¬ 
necting-rods are made of the best material, and the bearings are 
ample and well proportioned. The workmanship is excellent, and 
the finish neat and attractive. In fact, these engines rank among 
the most simple, durable, and economical in the country. They 
are manufactured by the Putnam Machine Company, Fitchburg, 
Mass. 



THE ENGINEER’S HANDY-BOOK. 


141 


How to put an Engine in Line. 

An engine is in line when the axis of the cylinder and the 
piston-rod are in one and the same straight line in all positions. 
This line extended should intersect the axis of the engine-shaft, 
and be at right angles to it. The guides should also be parallel 
thereto. The shaft must be level, but the centre line of the cyl¬ 
inder may be level, inclined, or vertical, according to the design 
of the engine. 

To “line up” an engine, as it is generally termed, take off 
the cylinder-head, remove the piston, cross-head, and connecting- 
rod ; then with a centre punch make four (4) marks in the counter¬ 
bore at each end of the cylinder, at equal distances apart round 
the bore. Take a piece of stiff hoop-iron with a hole at one end 
of it, slip it on to one of the stud-bolts of the back cylinder-head, 
and secure it firmly with a nut, after which it may be bent in the 
shape of a crank, one end projecting across the cylinder at its 
centre, at a sufficient distance from it to admit of convenient and 
accurate measurement. Next draw a fine line through the cylin¬ 
der, and attach one end of it to the temporary crank above men¬ 
tioned, and the other end to a stake driven into the floor at the 
back end of the bed-plate. Then with a piece of hard wood or 
stiff wire pointed at each end and equal in length to half the 
diameter of the cylinder, set the line so that, when one point of 
the wood or wire is inserted in any one of the centre-punch marks 
at either end of the cylinder, the other end will feel the line. Next 
see if this line passes through the centre of the shaft; if so, the 
cylinder is in line with the shaft; if not, one or the other must 
be moved, which requires both skill and judgment, since engines 
differ so much in design and construction. Now turn the engine- 
shaft round till the crank-pin almost touches the line passing 
through the centre of the cylinder; then ascertain by measure¬ 
ment whether the line is equidistant from the collars on the 
crank-pin. Then turn the shaft on the other centre until the 
crank-pin feels the line. If the measures correspond, the shaft 


142 


THE ENGINEER’S HANDY-BOOK. 


is in line with the cylinder; if not, they will show which end 
needs to be moved. The operation may have to be gone over 
several times before a definite conclusion can be arrived at. The 
shaft may be levelled by placing a spirit-level on it, if there be 
room ; if not, drop a plumb-line passing through the centre of the 
crank-pin and shaft; then by placing the crank at both centres 
and at half-stroke, the line will show whether the shaft is level or 
not. The guides may be brought into line with the cylinder, by 
measuring from each end of each guide to the line passing through 
the centre of the cylinder, and moving them until they are par¬ 
allel to the line and to each other. To adjust them to the hori¬ 
zontal, a spirit-level may be placed on their top faces. If no level 
is at hand, a square and plumb-line may be used. Where these 
accessories are not at hand, a straight-edge placed across them 
will determine by actual measurement whether they are in line 
with the centre line of the cylinder or not. 

Engines get out of line from the following causes: Faults of 
design, faults of construction, overwork, the character of the work 
which they are performing, or from the boss of the crank wearing 
away the face of the main bearing against which it revolves. To 
move an engine-shaft and pillow-blocks into line with the centre 
of the cylinder, screw down the caps of the pillow-blocks firmly 
on the shaft; then slack up on the bolts that tie down the pillow- 
blocks to the bed-pla*te, after which the shaft pillow-blocks and 
fly-wheel may be moved from the back end by means of a lever 
or jack-screw, after which they should be firmly tied and the set¬ 
screws or wedges readjusted. To move a cylinder, if the connec¬ 
tions be short and stiff, remove the bolts which tie it to the bed¬ 
plate ; then measure from the flange of the cylinder to some fixed 
object, such as a wall, post, or column ; cut a plank or scantling 
about an inch longer than the actual measurement from the cyl¬ 
inder to the wall, so that when placed against the cylinder it may 
stand slightly oblique; then by driving on the end of the plank 
with a sledge or heavy hammer, the cylinder may easily be moved. 
The holes should then be reamed, and new bolts corresponding to 










THE ENGINEER’S HANDY-BOOK. 


143 


the reamer substituted for the old ones. The cylinders, guides, 
and pillow-blocks of all engines should be double-pinned to pre¬ 
vent them from getting out of line; and whenever it becomes 
necessary from wear to move them, the holes may be re-reamed 
and new pins substituted. 

How to Set Up a Stationary Engine. 

The first object to determine in setting up steam-engines is to 
decide definitely the precise point at which the engine is to be 
located, after which the excavation for the. foundation may be 
made. It should be at least two feet wider and longer than the 
intended brick- or stone-work, and its depth must depend on the 
size and weight of the engine and character of the soil. For ordi¬ 
nary sized engines, say from 20 to 40 horse-power, from 3 to 4 
feet will suffice, if the soil is dry and firm ; but if sandy or swampy, 
it will require to be sunk deeper. For large engines of from 50 
to 100 horse-power it is necessary to find a solid bottom. There 
are even instances where piles had to be driven to insure a per¬ 
manent foundation. Too much care cannot be taken in this par¬ 
ticular, as any defect in the foundation will materially affect the 
working of the engine. 

Having decided on the location where the engine is intended to 
stand, line down from the side of the line of shafting, or counter¬ 
shaft, if there be any, to the floor, at three or four different places 
in its length; but if there be no shafting, measure from the side 
of the building to the centre, at five or six points in its length; 
then strike a line across all these points. This line will show with 
sufficient accuracy the line of the building by which the templet 
may be set up ; the latter, as shown in the cut on page 144, should 
be a fac-simile, or exact counterpart of the bottom of the bed-plate. 
It may be made of inch pine boards, and set on four props over 
the excavation, after which it must be squared and levelled with 
the lines previously taken. The anchor-bolts may now be hung 
in the templet, and the bricklayers proceed with their work. It 


144 


TIIE ENGINEER’S HANDY-BOOK. 


is customary to lay from two to three courses of bricks on the bot¬ 
tom of the foundation before the anchors are reached. These con¬ 
sist of plates of cast-iron or old boiler-plate, generally about a foot 
square, with a hole sufficiently large for the foundation bolts to 
slip through ; though in some instances the anchors extend entirely 
across the foundation and take in tyvo bolts each. 



The foundation should be widest at the bottom, and slope up¬ 
wards about 2 inches to the foot, till the level of the floor is 
reached, after which it may be carried up straight. When fin¬ 
ished, it may be an inch wider on each side and end than the 
bed-plate; after which it should be made perfectly level by means 
of a coat of good, strong mortar or cement. A parallel piece of 
pine wood, 1 inch in diameter and from 3 to 4 inches wide, made 
perfectly straight on both edges, on which a spirit-level may be 
placed, will answer for levelling the foundation. 

After the foundation is level, the bed-plate may be placed on it, 
either by means of a crane, block and tackle, or skids and block¬ 
ing, after which it may be tied down and accurately levelled. It 
is customary, in the case of large engines, to place wedges between 
the bed-plate and foundation, for the purpose of leaving an inter¬ 
stice between the bottom flange of the bed-plate and the brick 
work, into which melted sulphur is poured. As sulphur is less 
















THE ENGINEER’S HANDY-BOOK. 


145 


influenced by a change of temperature than any other known 
mineral, it is of great value as a bedding for heavy steam-engines, 
and other machinery; besides, when melted, it enters every 
crevice, and as soon as it is set becomes a permanent fixture. To 
use it, it is necessary to seal the opening between the bed-plate and 
brick work, inside and out, with potter’s clay, occasionally leaving 
a gate or “sprue” through which the molten sulphur is poured. 

A line should next be accurately drawn through the centre of 
the cylinder, and attached to some permanent object at the back 
end of the bed-plate; another line should be drawn at right angles 
to this through the centre of the main bearing; this latter will 
give the exact location of the off pillow-block, as the crank-shaft 
must be exactly at right angles with the horizontal line passing 
through the centre of the cylinder. The fly-wheel may next be 
swung into the pit, and the shaft slipped through it and firmly 
keyed at the right position, after which the pillow-block caps 
may be screwed down, the front head of the cylinder put on, the 
cross-head placed in position, the piston slipped in, and the con¬ 
nection between the cross-head and crank-pin made up. Other 
numerous details might be mentioned, but they never all apply to 
any individual case, and when any of them present themselves as 
the work proceeds, the remedy in this case must be prescribed by 
the erecting engineer. In setting up engines, like setting valves, 
only general instructions can be given, and it is impossible to lay 
down any that would apply to each and every case. 

How to Reverse an Engine. 

Place the crank on the dead-centre and remove the bonnet of 
the steam-chest; observe the amount of lead or opening that the 
valve has on the steam end; then loosen the eccentric and turn it 
round on the main shaft in the direction in which it is intended 
the engine should run, until the valve has the same amount of 
lead on the other end. To determine whether the lead is exactly 
the same at both ends, a small piece of pine wood may be tapered 
13 K 


146 


THE ENGINEER’S HANDY- BOOK, 

in the shape of a wedge, and inserted in the port; the marks left 
on it by the edge of the port and the lip of the valve will show 
how far it has entered. The engine should then be turned on the 
other centre for the purpose of equalizing the lead; the crank 
should also be placed at half-stroke, top and bottom, for the pur¬ 
pose of determining whether the port opening is the same in both 
positions. When the crank is at half-stroke, the centre of the 
crank-pin is plumb with the centre of the crank-shaft. 

How to Repair Steam-Engines. 

It would be reasonable to suppose that any machinist would 
be capable of repairing steam-engines; and yet, on an examination 
of numerous cases where repairs have been done by persons calling 
themselves mechanics, it appears that very few machinists are fit 
to be trusted to do so. A man to be competent to do repairs must 
first understand the original character of the engine or machine, 
and its defects, whether arising from design, inferior material, or 
workmanship, how an improvement can be made in its working, 
as well as what would be actually an improvement, before pro¬ 
ceeding to make it. 

The first step in repairing an engine is to take off* the connect¬ 
ing-rod, cross-head, both cylinder-heads, and remove the piston ; 
then pass a line exactly through the centre of the cylinder, and 
attach it to some fixed object at the back end, to determine if the 
centre of the crank-pin is in line with the centre of the cylinder. 
If not, one of them must be moved, and whichever it is will de¬ 
pend on the difficulty to be encountered, and must be determined 
by the judgment of the party who undertakes the repairs. The 
cylinder must next be accurately measured at both ends and the 
centre, for the purpose of determining if it is worn larger in the 
centre than at either end, or worn oval, as is often the case. 

In either case it will be necessary to rebore the cylinder and 
make it uniform all through. It is next necessary to caliper the 
cross-head, wrist- and crank-pin, to see if they are worn oval, and 


147 


THE ENGINEER’S HANDY- BOOK. 

if so, they must be filed round. The guides should then be tested 
with an accurate parallel piece, to ascertain if they are straight 
all through ; if they are hollow in the middle or at either end, 
they must be taken down and planed straight. If the piston-rod 
is badly fluted, it must be put in a lathe, returned, and filed; the 
rings should be taken off* placed in a lathe-chuck, and faced up 
on both ends, and if they are cut they should be turned true and 
smooth. The cross-head should then be measured crosswise to 
determine whether the guides are too far apart or not; and if so, 
the holes in the studs which tie them to the bed-plate must be 
filed oval to bring them to a proper position. If the valve and 
seat are cut, the valve must be taken off* and planed in the oppo¬ 
site direction to its travel. The steam-chest must also be removed, 
and the valve-seat straightened by filing and scraping, after which 
the valve may be carefully fitted to it. 

The flange of the piston-head and follower-plate should be faced 
up in a lathe, at the point where they strike the rings, and the lat¬ 
ter should be carefully ground and scraped on to them. The piston 
should next be inserted into the cylinder, set out, and the cross¬ 
head slipped on, connected with it, and levelled, so that it may 
stand parallel with the centre of the axis of the cylinder at all 
points of the stroke. The connecting-rod boxes should be ex¬ 
amined in order to ascertain if they are “brass bound,” and if so, 
they should be filed out. The main pillow-block bearing should 
receive attention, in order to determine if it is worn oval or loose. 
In fact, every part should receive attention, because defects that 
have not been thought of may be revealed as the work progresses. 
It has been generally heretofore supposed that any one bearing 
the name of a machinist is competent to repair a steam-engine, 
which, of course, is a grave error, as thousands of mechanics fully 
competent to build a machine are totally unfit to repair it. 

This arises from the fact, that the repairing of steam-engines 
and other machinery requires a different class of talent from that 
necessary to build them. A machinist may be a good hand on 
either a vice, lathe, or planer; he may be a thorough fitter and a 


148 the engineer’s handy-book. 

neat finisher, and yet lie may lack that keen observation, that cool, 
patient, and searching perseverance which are so essential in the 
party that will become an adept in the repairing of steam-engines 
and other machinery. It not unfrequently happens, that when 
everything has been done that was considered absolutely neces¬ 
sary, an engine works badly when started up, which is very dis¬ 
couraging to any one, except those who take a peculiar interest in 
ferreting out the causes of minor defects which have been over¬ 
looked when the more prominent ones were remedied. Almost 
any one can tell if an engine is badly out of line, the cylinder 
fluted, or the crank-pins loose or worn oval; but it requires a dif¬ 
ferent kind of talent to determine the different causes for the 
defective working of steam-engines, and prescribe a remedy for 
them, as many of them apparently did not exist at the commence¬ 
ment of the work, but cropped out as it progressed. One of the 
greatest mistakes in the repairs of steam-engines and other ma¬ 
chinery, is that those who have them in charge are expected to per¬ 
form the work in too limited a time. This being impossible, the 
only resource left is to slight it. 

How to Increase the Power of the Steam-Engine. 

It frequently happens that engines which were originally of 
sufficient power to do the work of a manufacturing establishment, 
become unable to do the work, owing to an increase in the busi¬ 
ness; and while the cost of replacing an engine with one of suffi¬ 
cient power would be a matter of nominal consideration, the time 
expended in removing and replacing it with a larger one might 
involve a serious loss to the owner, in case he had large orders for 
goods to fill at profitable prices. Under such circumstances, the 
three most practicable ways to remedy the difficulty for the time 
being would be— first, to raise the pressure, providing the boiler 
is considered safe; second, to increase the speed of the engine; 
third, to replace the old cylinder with a new one about two inches 
larger in diameter, which would of course involve the necessity of 
a new piston, steam-chest, and valve. 


THE ENGINEER^ HANDY-BOOK. 


149 


For a moderate increase in power, the last plan would be the 
most safe and practicable, as the active condition of steam-boilers 
is not always understood, and without a thorough knowledge on 
the subject it would be unwise to increase the pressure; nor should 
any engine be run at a higher speed than it is capable of stand¬ 
ing without springing or shaking to pieces. The increase in power 
that would result from replacing the old cylinder with a new one 
two inches larger in diameter may be illustrated as follows: Take, 
for instance, a 10-inch cylinder, which contains 78*54 square inches 
in area, while a cylinder 12 inches in diameter contains 113*09 
square inches, which makes a difference of 34*55 square inches in 
the piston. Now t , if the engine having a 10-inch cylinder was 
unable to do the work with 60 lbs. pressure per square inch, it 
would do the work easily with the 12-inch cylinder at the same 
pressure, as the new cylinder would make a difference of from 5 
to 6 horse-power. Measures might be taken, and the new cylin¬ 
der, piston, and steam-chest prepared and placed in position at a 
given time, without causing any interruption to the business. 

Of course the margin for increasing the size of cylinder for any 
engine, and using all the other original parts of the engine, is lim¬ 
ited, and should never exceed 2 inches; as, to exceed that limit, the 
other parts would be too light, and become liable to spring. To 
increase the speed of an engine, it would be necessary to have a 
new counter-pulley, so that, while the piston velocity is increased, 
the speed of the shafting may remain the same. An engine will 
develop more power by increasing its speed, but will use more 
steam, and as a consequence more fuel will be consumed. The 
overtaxing of steam-engines and boilers, or any other class of 
machines, is sure to induce waste either in fuel or wear and tear; 
but there are circumstances under which manufacturers and steam 
users find themselves placed, in which it would be impossible to 
avoid waste. Steam-engines or boilers, or any other class of 
machines that is too large or too small for the work to be per¬ 
formed, are not economical. 

13 * 


150 


THE ENGINEER^ HANDY-BOOK. 



The Greene Automatic Cut-Off High-Pressure Engine. 

The following cut represents the Greene Automatic Cut-Off 
Engine, manufactured by the Providence Steam-Engine Co., P. I. 
This company uses two styles of bed-plate, one of which is known 
as the side-bed pattern, in which the cylinder and slides are secured 

to the sides of the bed-plate, 
and the main bearings cast 
on — thus securing rigidity 
and strength, without any 
extra weight of material. 
The other bed-plate (as 
shown in the illustration) is 
of the box pattern, on which 
the cylinder is secured by 
means of tapering, reamed 
bolts, thereby preventing the 
engine from getting out of 
line. The slides and main 
bearings are cast separate, 
planed, accurately fitted, and 
secured with dowels. The 
main journal-boxes are made 
in four pieces, and are pro¬ 
vided with set-screws and 
check-nuts, which permit of 
convenient and accurate ad¬ 
justment. 

The governor is of the 

ordinary fly-ball pattern; it 
is suspended from a bracket 
attached to the steam-pipe, 
and is driven by a belt di¬ 
rectly from the main shaft. 
The regulation of the speed is obtained by a rack on the governor- 



















151 


THE ENGINEER’S HANDY-BOOK. 

spindle, which is operated by toothed segments on the inner ends 
of the ball-arms, by which a rising of the balls produces a lower¬ 
ing of the rod and a shortening of the cut-off, and vice verm. The 
valve-gear is detachable, and is so controlled by the governor that 
the cutting off may be effected from one-quarter to three-quarters 
of the entire stroke. The valves are four in number — two steam 
and two exhaust — and are of the flat-side pattern. The power 
which moves them is applied parallel to, and nearly in line with, 
their seats, so that they cannot rock or twist—thus obviating the 
tendency to wear unevenly. The steam--valves, when tripped, are 
shut by the combined action of a weight and the pressure of the 
steam on the large valve-stems, thereby insuring a quick cut-off, 
and the positive closing of the port, under all circumstances of 
speed and pressure. The steam-valves are operated by toes, on 
the inner ends of two rock-shafts that connect with the valve- 
stems, outside the steam-chest. The outer ends of the rock-shafts 
are furnished with steel-tipped toes. 

Below these is a sliding-bar, carrying the tappets and receiving 
a reciprocating rectilinear motion from an eccentric on the main 
shaft. Behind the sliding-bar is a gauge-bar (shown on the front 
of the cut) connected with the governor, which bar receives an 
up and down motion — from a reverse action of the governor-balls. 
The tappets in the sliding-bar are kept in contact with the gauge- 
bar, and are made to move up and down with it by springs. As 
the sliding-bar moves in the direction of the arrow, one of the 
tappets is brought in contact with the inner face of the toe on the 
rock-lever, causing it to turn on its axis, thereby opening the 
steam-valve at one end of the cylinder; the other tappet, mean¬ 
while, passes under the other rock-lever, without moving it — the 
toe and tappet being so bevelled that the tappet will be forced 
down, against the action of the spring, till it has passed the toe, 
when the spring causes it to resume its original position, prior to 
opening the steam-valve at the opposite end of the cylinder upon 
the return stroke of the bar. 

As a result of this motion, the tappet always gives the valves 


152 


THE ENGINEER^ HANDY-BOOK. 


the same lead, and as the bar moves in a straight line, while the 
toe describes the arc of a circle, the tappet will pass by and liberate 
the toe, which is brought back to its original position by a weight, 
and the steam pressure on the large valve-stem, which thus closes 
the valve and cuts off the steam. The liberation of the toes will 
take place sooner or later, according to the elevation of the tappet; 
that is, the lower the tappets are, the sooner the toes will be liber¬ 
ated, and vice versa. By the elevation or depression of the gauge- 
bar, the period of closing the valves is changed, while the period 
of opening them remains the same. The adjustment of the gauge- 
bar is effected directly by the governor. 

The exhaust-valves are within the cylinder, and are exposed to 
view by removing the cylinder-heads. They receive their motion 
from a separate eccentric, thus allowing of easy adjustment with¬ 
out interference with the steam-valve mechanism. All the con¬ 
nections are on the outside, are few in number, and have ample 
bearing surfaces, insuring freedom from rapid wear and derange¬ 
ment. 

The design and arrangement of the Greene engine embody 
some excellent features. The ports are large, thus insuring the 
full pressure of steam on the piston to the point of cut-off. All 
the parts are well proportioned, made of the best material, accu¬ 
rately fitted, and splendidly finished. They work with uncommon 
smoothness and regularity, and present a very agreeable and sym¬ 
metrical appearance. They have the reputation of being the most 
durable, economical, and efficient engines in the country. 

The Dead-Centre. 

All reciprocating steam-engines have one dead-centre in each 
stroke and two in each revolution, and that point is the point at 
which the steam is exhausted, and the centre of the crank-pin is 
parallel with the centre of the axis of the cylinder. The centre 
of the cross-head, in some cases, may be above or below the centre 
of the cylinder; but by placing a spirit-level on the top or bottom 


THE ENGINEER’S HANDY-BOOK. 


153 


of the stub-end strap, the dead-centre may be easily found. The 
experienced engineer or machinist can generally tell by the eye 
when the crank is at the dead-centre; but to insure accuracy it 
is always better, in the case of horizontal engines, to try it with a 
level, and in vertical engines with a plumb-bob and line. The 
cranks of all engines have to be placed accurately on the centre 
when the valves are set. 

A single reciprocating engine is completely helpless when the 
crank is at the dead-centre, and would stop there if it was not for 
the momentum of the balance-wheel. Double reciprocating en¬ 
gines, such as locomotives and marine engines, which have their 
cranks set at right angles, require no balance-wheel, as they pull 
each other off the dead-centre, in consequence of one crank being 
at its full-power point while the other is at the weakest. There 
are some engines, such as the rotary, which have no dead-centre 
in their revolution. 

Tlie Causes of Knocking in Steam-Engines. 

The most frequent causes of knocking in steam-engines are 

lost motion in the cross-head, wrist- and crank-pin boxes; loose¬ 
ness in the pillow-block or main-bearing boxes; looseness of the 
piston-rod or folhnver-plate; the crank-pin or crank-shaft being 
out of line with the cylinder, or the wrist-pin, crank-pin, or main- 
bearing journal being worn oval; the slide-valve having too much 
or not enough lead ; the exhaust opening being too soon or too late; 
the valve being badly proportioned, or the exhaust passage out¬ 
side of the cylinder being contracted. 

Other causes are shoulders being worn in each end of the 
cylinder, in consequence of the packing-rings not travelling over 
the counter-bore at each end of the stroke; or shoulders being 
worn on the guides, resulting from the cross-head shoes not over¬ 
lapping them when the crank is at the dead-centre; the piston 
not having sufficient clearance at either end of the cylinder, in 
consequence of its being altered by taking up the lost motion in 


154 


THE ENGINEER^ HANDY-BOOK. 


the boxes ; there not being sufficient draught in the keys to take up 
the lost motion in the connecting-rod boxes; the packing being 
screwed too tight round the piston-rod; excessive cushioning, re¬ 
sulting from the leaky condition of the piston, which allows the 
steam to occupy the space between the cylinder and piston-head, 
as the crank approaches the centre, thereby subjecting the engine 
to an enormous strain, as at this part of the stroke the fly-wheel 
is travelling very fast and the crank moving very slowly; or lost 
motion in the connection by which the slide-valve is attached to 
the rod. Engines out of line frequently knock sideways at the 
half-stroke, but most generally at the outward or inward, upper 
or lower dead-centre, as these are the points at which the greatest 
strain is thrown on the bearings, m consequence of the direction 
of the connecting-rod having to be reversed. The foregoing causes 
of knocking in engines constitute the principal ones. 

The knocks arising from lost motion in any of the revolving, 
reciprocating, or vibrating parts of an engine may be located by 
placing the finger on the part, while the cross-head is being re¬ 
moved back and forth on the guides by the starting-bar; but 
knocks induced by the valve opening or closing too soon, by a 
contraction of the exhaust, or by the valve or valves being im¬ 
properly set, are the most difficult to discover, as they are different 
from those induced by lost motion, the sound being a dull, heavy 
thud, in many instances causing the engine, building, and even the 
foundation to vibrate at every stroke. While an intelligent and 
careful search will in most cases result in successfully locating the 
knock, some will for a time baffle the most expert engineer. In¬ 
stances are not uncommon in which weeks have been devoted, en¬ 
gines taken apart and put together again, to find a knock, which, 
when finally discovered, perhaps turned out to be caused by a 
loose crank-pin, follower-plate, or key in a fly-wheel. It not un- 
frequently happens that, after every other means have been re¬ 
sorted to, the indicator has to be applied, in order to determine 
the precise location of the knock or “thud.” 

From whatever causes knocking in engines may arise, they are 


155 


the engineer’s handy-book. 

a nuisance, which sounds harshly not only to the engineer, but to 
all who have an ear for natural mechanics. Nothing, perhaps, 
makes the intelligent engineer feel so cheap as to be found in 
charge of an engine that knocks, as lookers-on are not always 
capable of deciding who is at fault — the engine or the engineer. 

The Remedies for Knocking in Steam-Engines. 

While it may be possible in most cases to locate the knocking 

in steam-engines, and explain the causes from which they arise, it 
is hardly possible to prescribe a remedy for all, as, in many in¬ 
stances, it must arise out of and be determined by the circum¬ 
stances of the individual case. The most practical method of 
remedying the knocking induced by the crank-pin being out of 
line, is to place the crank-shaft at right angles with the centre of 
the cylinder, remove the old crank-pin, rebore the hole so as to 
bring the centre of the new pin perfectly in line with the axis of 
the cylinder, and replace the old pin with a new one. The knock¬ 
ing induced by the wrist-pin and crank-pin becoming worn oval, 
may be remedied by filing them perfectly round; but the knock¬ 
ing caused by the crank-shaft journal being worn out of round is 
very difficult to remedy; in fact, there is hardly any remedy for 
it, except to remove the shaft, true it up in a lathe, and refit the 
boxes, which operation is attended with a good deal of difficulty, 
more especially when the engine is large. 

Knocking in the boxes on the crank-pin and cross-head, or 
valve-rod, may be remedied by filing out the boxes and readjust¬ 
ing the keys, or by putting a liner behind or in front of the boxes, 
when there is not sufficient draught in the keys and gibs. Knock¬ 
ing in the steam-chest caused by looseness in the valve connec¬ 
tions may be remedied by readjusting the jam-nuts or the yoke. 
Knocking arising from this cause manifests itself more frequently 
when steam is shut off from the cylinder, preparatory to stopping 
the engine, than when the engine is running; the lost motion is 
taken up in the valve connections by the pressure of the steam 
on the back of the valve. 


156 


the engineer’s handy-book. 


Knocking in the piston is generally caused by the rod becoming 
loose in the head, and, if it continues for any length of time, it 
destroys the fit of the rod in the hole. The only practical remedy 
under such circumstances is to remove the rod, rebore the hole, 
and bush it or thicken the rod at that point by welding, and lit it 
to the head after the hole is rebored perfectly true. Knocking in 
the follower-plate is generally caused by the bolts being too long, 
or from dirt being allowed to accumulate in the holes, which pre¬ 
vents them from entering sufficiently far to take up the lost mo¬ 
tion in the plate, and may be remedied by shortening the follower- 
bolts, or removing the deposits from the bottoms of the holes, as 
the case may be. 

The knocking caused by shoulders becoming worn in the cyl¬ 
inder at each end can be remedied by reboring the cylinder, and 
making the counter-bore sufficiently deep that a part of one of 
the rings will overlap it at each end of the stroke. Knocking 
caused by shoulders becoming worn on the guides can be remedied 
by planing the guides and making the gibs or shoes sufficiently 
long that they will overrun the guides when the crank is at either 
centre. The knocking induced by any of the foregoing causes is 
generally a source of great annoyance to the engineer, as any at¬ 
tempt to adjust the boxes on the cross-head or crank-pin, or the 
piston-packing in the cylinder, generally aggravates the cause of 
the knocking, as any adjustment of the connecting-rod boxes alters 
the position of the piston in the cylinder and the cross-head on 
the guides, and causes them to strike harder against the shoulders. 

Knocking caused by the valve or valves being improperly set 
may be remedied by removing the bonnet of the steam-chest and 
adjusting the valve, so that it may move uniformly on its seat, 
thereby giving the same amount of lead at each end of the stroke ; 
then, if the valve is well proportioned, and the connections thor¬ 
oughly fitted and skilfully adjusted there is no reason why the 
engine should knock from this cause. But the knocks arising 
from bad proportion in the valve or steam passages are the most 
difficult of all to remedy, as they are inherent in the machine. 


Front View of the Douglas Automatic Cut-Off Engine. 














































































































































































































































































158 


BOOK 







































































































































































































































































THE ENGINEER’S HANDY “BOOK. 


159 


The Douglas Automatic Cut-Off Engine. 

The cuts on pages 157, 158, represent the Douglas Automatic 
Cut-Off Engine. It will be noticed that the hed-plate is of the 
girder-frame pattern, which is faced up to receive the cylinder at 
one end and the main pillow-block bearing at the other. The 
cylinder rests on a tapering pedestal, while the back end of the 
bed-plate and crank-shaft bearing is supported by a double leg, 
which is cast solid with the bed-plate. The pillow-blocks at the cyl¬ 
inder-base are placed on the under side, and are situated at equal 
distances from the centre, which facilitates the setting up of the 
engine or placing it in line, as all that is necessary is to level 
the foundation stone and place the engine on it. The cross-head 
guides are bored out cylindrical, and on line with the centre of 
the cylinder, which obviates the liability of the engine getting 
out of line. 

The main steam-valve serves both for induction and exhaust. 
The exhaust passes through its centre to the exhaust-port at the 
centre of the cylinder. It receives its motion from an eccentric, 
through the intervention of a rocker-arm and small take-up connect 
tions from the rocker-arm to the valve-rod. The two cut-off valves 
are flat, and slide on the top of the main valve. They receive 
their motion from an extra eccentric and rocker-arm. On this 
rocker-arm is a disc, pivoted on its centre. At equal distances 
from the pivot-pin, in opposite directions, are two wrist-pins, to 
which the cut-off valve on the frame end is attached by a take-up 
connection and spade-handle joints to the lower pin of the disc, 
while the steel rod passing through the sleeve to move the other 
cut-off valve is attached to the other pin on the disc. The lever 
and connection attachments from the governor to the rocker and 
disc rotate either way, separating the cut-off valves or drawing 
them nearer together, cutting off the steam earlier or later in the 
stroke, to accommodate a varying load and pressure. 

The governor is very powerful, sensitive, and positive in its ac¬ 
tion, and can be driven by either belt or gearing. Should the belt 


160 


THE ENGINEER’S HANDY-ROOK. 


shrink or slip off, the engine would continue to run the same as be¬ 
fore it broke, as there would be no power to change the valves, since 
the centrifugal force has only the clutch-back and the centre-weight 
to lift. The driving power of the governor, when the clutches 
are in contact, acting on a clutch attached directly to the top of 
the screw, turns it up, and, acting on a clutch attached to the re¬ 
versed gear, turns it down. It turns the screw up or down out 
of clutch before the governor can make a revolution. 

The pillow-block boxes are lined with Babbit metal, and are 
provided with wedge- and draw-screws for the purpose of taking 
up the wear and lost motion. The wrist- and crank-pins, valve- 
and piston-rods, are made of steel well proportioned and well fitted. 
The fly-wheels are turned off on the face and sides and are accu¬ 
rately balanced. The Douglas engines are in very general use in 
the Western States and Territories, and wherever used their repu¬ 
tation for efficiency, durability, and economy has added to their 
credit. 

Technical Terms Applied to Different Parts of 

Steam-Engines. 

Bonnet. — This term is applied to the covers of the steam-chest. 

Brasses. — This term is understood to apply to the wrist- and 
crank-pin, or connecting-rod boxes; but it is used in connection 
with other arrangements. 

Counterbore. —A term applied to recesses in the ends of steam- 
cylinders in the clearance space, over which the piston-rings 
partly travel. The object of the counterbore is to prevent 
shoulders being formed at each end of the cylinder, which would 
induce knocking in the engine when any changes are made in 
the connecting-rod brasses. 

Jam-nuts. — A term applied to the nuts which lock the adjust¬ 
ing-screws in the piston- and valve-gear of steam-engines; but 
jam-nuts and lock-nuts are used for many other purposes in 
connection with the steam-engine. 


THE ENGINEER’S HANDY-BOOK. 


161 


Pipe-swivel. — A long nut containing a right- and left-hand 
thread. It is used for adjusting the valve-gear of steam-engines, 
particularly those of the Corliss type; but the pipe-swivel is used 
lor many other purposes than this. 

Trunk. —A term applied to the hollow tube connected with 
the pistons of trunk engines in which the connecting-rod oscil¬ 
lates. The term is just as applicable to certain other parts of 
machinery and arrangements as to the steam-engine. 

Trunnions. — A term applied to the gudgeons on which the 
cylinders of oscillating engines vibrate; but it may be, and often 
is, applied to other machinery as well as oscillating engines. 

Terms Formerly Applied to Different Parts of Steam- 
Engines, but which have become Obsolete. 

Gab-lever. —A term formerly applied to an arrangement used 
for lifting and lowering the eccentric-hook off and on the rocker- 
pin. 

Pitman. —A term applied to the crank-pins of steam-engines 
in early times. 

Plug-tree. —A primitive valve-gear which superseded the 
scoggin. 

Radius-bar. —A term applied to the connecting-rods of engines 
in the early days of steam engineering. 

Scoggin. —This name was given by the boy Potter to the ar¬ 
rangement he invented for opening and closing the valves ol 
steam-engines. 

Shackle-bar. —This term was used to denote the connecting- 
rod of steam-engines at a period when they were generally made 
of wood, and strapped with iron at both ends. 

Spider. —The primitive name for piston-heads of steam-engines. 

14 * L 


162 


THE ENGINEER’S HANDY-BOOK. 


Questions: 

THE ANSWERS TO WHICH WILL BE FOUND IN THE TEXT. 

Into what two classes are steam-engines divided, regardless of 
design, general arrangement, etc. ? 

Into what two classes are steam-engines in general sub-divided? 

Explain the difference between condensing and non-condensing 
engines, their advantages and disadvantages, and their difference 
in useful results. 

What are the advantages of compound oversimple engines, and 

vice versa t 

\ 

State the formulae for estimating the power of each class of 
engines. '' 

Explain the difference between automatic cut-off and throt¬ 
tling engines, and the advantages of the one over the other. 

Explain the advantages and disadvantages of the various cut¬ 
offs employed on stationary, marine, and locomotive engines. 

What are the most valuable features in any steam-engine? 

What advantages are derived from duplicating the parts of 
steam-engines ? 

How would you proceed to fit the crank of a steam-engine on 
its shaft? 

How would you proceed to set up a stationary engine? 

How would you proceed to repair a steam-engine? - 

What is the meaning of the term “ dead-centre ” ? How would 
you proceed to find it ? 

Explain the general causes of knocking in steam-engines, and 
the remedies for the same. 


THE ENGINEER’S HANDY-BOOK. 


163 


PART THIRD. 


Bed-Plates and Housings. 

The bed-plate is that part of a steam-engine which forms the 
connection between the cylinder and the main pillow-block or 
crank-shaft, and, in many instances, constitutes the support on 
which they rest. They embrace a great variety of shapes and 
forms, such as the box side bed-plate, girder-frame, etc., which 
were all doubtless designed to meet some peculiar requirement, 
and for each of which special advantages are claimed, the girder- 
frame being in most favor with modern engineers. This is in 
part due to the fact, that the necessary rigidity can be obtained 
with less metal than in any other form, and that the strength can 
be more equally distributed in the line of the strain, and above 
and below it. Bed-plates are subjected to transverse in addition 
to tensile and compression strains. 

In designing a girder-frame, if it is to be supported only 
at the ends, due allowance must be made for transverse strains 
due to the thrust of the connecting-rod. The amount of this 
strain may be found by dividing the greatest pressure to which 
the piston may be subjected at mid-stroke by the quotient ob¬ 
tained by dividing the connecting-rod by the crank. Thus, sup¬ 
pose the area of the piston is 200 sq. inches, and it is desired to 
give ample strength for, say 80 lbs. of steam at mid-stroke; 
200 x 80 = 16,000 lbs., the force on the piston. Then suppose 
the quotient obtained by dividing the connecting-rod by the crank 
is 5 ; 16,000 -s- 5 = 3200 lbs., the pressure on the slides at mid¬ 
stroke. When the engine runs over, that is, when the top of the 
fly-wheel runs from the cylinder, the weight of the cross-head, 
and half the weight of the connecting- and piston-rods, must be 
added to this, and deducted when the motion is in the opposite 
direction. 



164 


THE ENGINEER’S HANDY-BOOK. 


When an engine runs under, a support under the frame at the 
slides (supposing the frame to be of the girder type) would not 
compensate for weakness of the frame, as the thrust of the con¬ 
necting-rod being upwards, the upper slide would give, however 
securely the lower one might be supported. The term housing is 
applied to the upright frames of both land and marine engines. 

The Housing. — This term is applied to the upright frame of 
vertical engines on which the cylinder rests, and which, at its base, 
contains the main pillow-block bearings. 

Steam-Cylinders. 

The cylinder is one of the most important as well as the most 
expensive parts of a steam-engine; it must be made of iron pos¬ 
sessing the qualities of hardness and toughness, be moulded and 
cast with great care, and bored with great accuracy. Cylinders, 
from the moment they are put into use, have a tendency to wear 
oblong, also to wear larger in some places than others. This in¬ 
volves the necessity of reboring them, which is one of the largest 
items of expense incurred in the repairs of a steam-engine. 

There are certain peculiarities connected with the wear of 
steam-cylinders upon which engineers have hitherto been unable 
to agree, among which is, why the cylinders of different engines 
of the same size, design, and manufacture, and under the same 
conditions, wear in opposite directions. The cylinders of some 
horizontal engines wear more on the lower than on the upper side, 
while others of the same size and build wear more on the sides 
opposite the ports, and others on the sides next the ports. Nor is 
it always the largest cylinders and heaviest pistons that wear most 
on the lower side of the cylinder. The same peculiarities hold 
good in relation to vertical engines. On some lines of ocean 
steamers, where four or five of the engines were built by the same 
manufacturing firm, and whose design, quality of material, char¬ 
acter of workmanship were intended to be as much alike in every 
respect as it was possible to make them, it was found on exaini- 


165 


THE ENGINEER’S HANDY-BOOK. 

nation that the cylinders of all were worn oblong — some in the 
middle, others at both ends, and others still at only one end. It 
is a general impression among engineers, that the cylinders of very 
large horizontal engines are more liable to wear oblong than those 
of vertical engines of the same bore; but experience and obser¬ 
vation have proved this to be a mistaken idea. A distinguished 
American mechanic, who has had more experience in boring out 
the cylinders of large stationary, locomotive, and marine engines, 
within the past ten years than any other party on this continent, 
asserts that there is no accounting for the manner in which steam- 
cylinders wear, and that in numerous instances he found the cyl¬ 
inders of the engines of ocean steamers worn oblong, the wear 
being as often on the sides next the ports as on those opposite. 
He also observed in horizontal engines, with cylinders 36 inches 
in diameter, that the wear on the bottom was hardly perceptible, 
while it was sufficiently apparent, on either one side or the other, 
to involve the necessity of reboring. 

This is a subject worthy of study and investigation, as on it 
depends a good deal of the economy of the steam-engine. Most 
engineers would be inclined to think that such freaks were due to 
a want of perfect alignment, as, with the piston, cross-head, crank- 
pin, perfectly true with the centre-line of the cylinder, and with 
each other, it is difficult to see why the piston should press-in any 
direction except that caused by gravity ; but most experienced 
engineers are aware that engines that are supposed to be per¬ 
fectly in line are not actually so, and a very little inaccuracy in 
the alignment of the slides, or in the cross-head guides, may suf¬ 
fice to press the piston out of centre. Even this may be aggravated 
by any unequal thickness of packing in the stuffing-box around 
the piston-rod. 

Rule for finding the proper thickness for steam-cylinders. 

Divide the diameter of the cylinder plus 2 by 16, and deduct 
a j^th part of the diameter from the quotient; the remainder 
will be the proper thickness. 

Rule for finding the required diameter of cylinder for an 


166 


THE ENGINEER’S HANDY-BOOK. 

engine of any given horse-power, the travel of piston and avail¬ 
able pressure being given. 

Multiply 33,000 by the number of horse-power; multiply the 
travel of piston in feet per minute by the available pressure in 
the cylinder. Divide the first product by the second ; divide this 
quotient by the decimal *7854. The square root of the last quo¬ 
tient will be the required diameter of cylinder. 

Rule for finding the cubic contents of a steam-cylinder. 

Multiply the area of cylinder in inches by the length of the 
stroke in inches, and divide this product by 1728. The quotient 
will be the number of cubic feet. 

TABLE 


SHOWING THE PROPER THICKNESS FOR STEAM-CYLINDERS FROM 6 TO 90 

INCHES. 


Diameter 

of 

Cylinder. 

Thick¬ 

ness. 

Diameter 

of 

Cylinder. 

Thick¬ 

ness. 

Diameter 

of 

Cylinder. 

Thick¬ 

ness. 

Diameter 

of 

Cylinder. 

Thick¬ 

ness. 

6 in. 

•440 

28 in. 

1 *595 

50 in. 

2*750 

72 in. 

3-905 

8 “ 

•545 

30 “ 

1-700 

52 “ 

2*855 

74 “ 

4-010 

10 “ 

•650 

32 “ 

1-805 

54 “ 

2-960 

76 “ 

4-115 

12 “ 

*755 

34 “ 

1-910 

56 “ 

3-065 

78 “ 

4-220 

14 “ 

•860 

36 “ 

2-015 

58 “ 

3-170 

80 “ 

4-325 

16 “ 

•965 

38 “ 

2-120 

60 “ 

3-275 

82 “ 

4-430 

18 “ * 

1-070 

40 “ 

2-225 

62 “ 

3*380 

84 “ 

4-535 

20 “ 

1-175 

42 “ 

2-330 

64 “ 

3-485 

86 “ 

4-640 

22 “ 

1-280 

44 “ 

2-435 

66 u 

3-590 

88 “ 

4-745 

24 “ 

1-385 

46 “ 

2-540 

68 “ 

3-695 

90 “ 

4-850 

26 “ 

1-490 

48 “ 

2-645 

70 “ 

3-800 




Rule for finding the quantity of steam any engine will use at 
each stroke of the piston. 

Multiply six times the area of the cylinder by ^ the stroke, and 
divide by 1728; the quotient is the cubic contents of the cylinder 
in feet. Divide this quotient by the cut-off 4, or 4 , as the case 
may be; the result will be the quantity of steam used at each 
stroke of the piston. 

Cylinder-head bolts. — There does not appear to be any uni- 






















THE ENGINEER’S HANDY-BOOK. 


167 


versal rule among steam-engine builders for proportioning tlie 
strength of cylinder-head bolts. In most of the prominent loco¬ 
motive works in this country, eleven -J bolts for an 18-inch cyl¬ 
inder are used; which practice is based on the assumption that 
150 lbs. of steam pressure per square inch is the maximum strain 
to which the area of the head can safely be subjected. Taking 
5800 as the sectional area of each bolt, and dividing by the total 
pressure of steam per square inch against the cylinder-head, we 
get the area of all the bolts required. This quotient, if divided 
by the area of one bolt, will give the whole number of bolts neces¬ 
sary. 

Fig. 1. Fig. 3. Fig. 2. 



The Babbit & Harris Steam-Piston. 


Steam-Pistons. 

The piston is one of the most important adjuncts of the steam- 
engine; all the other parts are subsidiary to it. No part of the 
steam-engine, since its advent, has proved a greater source of an¬ 
noyance to the engineer, and anxiety and waste to the steam user. 
It is well known that only about 10 per cent, of the energy stored 
up in good fuel is utilized in the best class of steam-engines; this 

































































































































168 


THE ENGINEER’S HANDY-BOOK. 


being a fact, however economically steam may be generated in 
the boiler; unless the piston is steam-tight and capable of resist¬ 
ing the strains to which it is subjected, very little of the work it 
should perform will be realized. 

There are strong reasons why every portion of an engine should 
be made as light as is consistent with strength; but this is espe* 
cially the case in the piston, from the rapidity of its reciprocating 
motion and the strains induced by the momentum on the crank- 
pin and other parts of the mechanism ; consequently, the essential 
requirements of a good piston are strength, lightness, simplicity, 
durability, and convenient arrangement for easy and accurate ad¬ 
justment. Though the U. S. Patent-Office is literally crowded with 
arrangements which are claimed to be improvements on all former 
devices, it is asserted by intelligent engineers that a good piston 
is as much of a necessity as it was in the days of Watt. Nor has 
it ever been definitely settled which of the steam-pistons now in 
use is best suited to all classes of engines; nor is it at all likely 
that any one piston will ever be able to establish its superiority 
under all circumstances. It may be said of steam-pistons, as of 
steam-engine governors, while they behave well in the majority 
of cases, there are circumstances under which the very best of 
them utterly fail to give satisfaction. 

The depth of the piston-pings, in good practice, should be about 
| the diameter of the cylinder, and the thickness of the follower- 
plate the same as that of the cylinder; so that the whole thick¬ 
ness of the piston will be j the diameter of the cylinder plus twice 
its thickness, as obtained by the foregoing rule. The diameter of 
the piston-rod should be from | to ^ that of the cylinder for high- 
pressure engines, and j for condensing engines. 

The cuts on page 167 show the Babbit & Harris Piston, which 
is in very general use, and is said to be very serviceable. No. 1 
represents the packing in its place; No. 2 shows the junk-ring, 
with two sections of packing out; No. 3, the said two sections. 

The inner ring of steam-piston packings, against which the 
springs press, is termed the junk-ring. 


169 


THE ENGINEER’S HANDY-BOOK. 

Piston-Rods. 

The diameter of piston-rods varies with different builders, the 
range being between ^ and y^ the diameter of the cylinder, ac¬ 
cording to their length and probable maximum pressure. The 
high-pressure piston-rods of the American line of steamships are 
about 4 the diameter of the cylinders, and the low-pressure about 
y 1 ^. The piston-rod of the Corliss Centennial Engine was about 
i the diameter of the cylinder. A rod T 'y the diameter would be 
the area of piston; and if 100 lbs. of steam were acting on 
the piston, the strain would be 10,000 lbs. per square-inch section 
of rod, which is about \ the breaking strength of good iron. 

But the strain on a piston-rod is alternately tensile and com¬ 
pressive. Such a size would evidently do for such a pressure, 
though it might not break so long as it was not subjected to any 
undue strains from accidental causes, such as water in the cylinder, 
etc. On the other hand, the largest size in use — J the diameter 
of the cylinder — would be ^ the area, on which the strain due 
to 100 lbs. of steam would be 3600 lbs. per square-inch section, 
which is fairly within the limits of perfect safety. But the 
pressure on the piston is not the main consideration in deter¬ 
mining the size of the rod, as accidental strains, to which it is 
liable to be subjected, must be adequately provided for. Some of 
these strains bear no relation to the steam pressure, so that the 
diameter of the piston should be made the main factor in de¬ 
termining the size of the rod. Bourne’s rule is to multiply the 
diameter of the cylinder in inches by the square root of the 
pressure on the piston in pounds per square inch, and divide 
the product by 50. The quotient is the size of the piston-rod. 

Piston-rods may be smaller in diameter than the foregoing, if 
made of steel, and if they possess sufficient rigidity and strength 
to resist all strains to which they may be exposed, and at the same 
time induce less friction, do more service, with less liability to flute 
or require returning, while the difference in first cost would be 
very trifling, and that of fitting about the same. 

15 


170 


THE ENGINEER^ HANDY-BOOK. 

TABLE 

OF UNITS OF HORSE-POWER FOR DIFFERENT PISTON SPEEDS. 

The following table will supply any units of horse-power, be¬ 
sides those already given, for any other velocity of piston by mul¬ 
tiplication or division. For example, a piston of 12 inches diam¬ 
eter, at 400 feet per minute, gives 1*366 horse-power for every 
pound average pressure on each square inch, and will give one-half 
or double this amount at speeds of 200 or 800 feet a minute. 


INDICATED HORSE-POWER FOR EACH POUND AVERAGE PRESSURE 
PER SQUARE INCH, WITH DIFFERENT DIAMETERS AND 
SPEEDS OF PISTON. 


tt «J 

3 © 

n zi a 

SPEED OF PISTON IN FEET PER MINUTE. 

a © .2 

oJ ■— 1 

S O 

240 

300 

350 

400 

450 

500 

550 

600 

Inches. 









4 

*091 

•114 

•133 

•152 

•171 

•19 

•209 

•228 

41 

*115 

•144 

*168 

•192 

•216 

•24 

•264 

•288 

5 

•144 

•18 

•21 

•24 

•27 

•30 

•33 

•36 

51 

•173 

•216 

*252 

*288 

•324 

•36 

•396 

•432 

6 

•205 

*256 

•299 

•342 

•385 

*428 

•471 

•513 

61 

•245 

*307 

•391 

•409 

•461 

•512 

•563 

•614 

7 

•279 

•348 

•408 

*466 

•524 

•583 

•641 

*699 

7 1 
' I 

•321 

•401 

•468 

•534 

•602 

•669 

*735 

*802 

8 

•365 

•456 

•532 

•608 

•685 

•761 

•837 

•912 

81 

*413 

•516 

•602 

•688 

•774 

•86 

•946 

1-032 

9 

*462 

•577 

•674 

•770 

•866 

•963 

1-059 

1-154 

91 

•515 

*644 

•751 

•859 

•966 

1-074 

1-181 

1-288 

10 

•571 

•714 

•833 

•952 

1-071 

1*390 

1-309 

1-428 

101 

•63 

•787 

•919 

1*050 

1-181 

1-313 

1-444 

1-575 

11 

*691 

•864 

1-008 

1-152 

1-296 

1-44 

1-584 

1-728 

111 

•754 

*943 

1-1 

1-257 

1-414 

1-572 

1-729 

1-886 

12 

•820 

1-025 

1*195 

1-366 

1*540 

1-708 

1-880 

2-050 

13 

•964 

1-206 

1-407 

1-608 

1-809 

2-01 

2-211 

2-412 

14 

1-119 

1-398 

1-631 

1-864 

2*097 

2-331 

2-564 

2-797 

15 

1*285 

1-606 

1-873 

2-131 

2*409 

2-677 

2-945 

3-212 

16 

1-461 

1-827 

2*131 

2-436 

2*741 

3 045 

3*349 

3-654 

17 

1-643 

2-054 

2*396 

2*739 

3*081 

3*424 

3*766 

4*108 

18 

1-849 

2*312 

2-697 

3-083 

3*468 

3-854 

4*239 

4-624 

19 

2*061 

2*577 

3-006 

3*436 

3-865 

4-295 

4*724 

5-154 

20 

2-292 

2*855 

3-331 

3*807 

4*265 

4*759 

5-234 

5-731 

21 

2-518 

3-148 

3*672 

4-197 

4-722 

5*247 

5*771 

6-296 

22 

2*764 

3 455 1 

4*031 

4-607 

5-183 

5-759 

6*334 

6-911 































171 


THE ENGINEER’S HANDY-BOOK. 


TABLE— ( Continued .) 

—— , 

INDICATED HORSE-POWER FOR EACH POUND AVERAGE PRESSURE 
PER SQUARE INCH, WITH DIFFERENT DIAMETERS AND 

SPEEDS OF PISTON. 


Diameter 

of 

Cylinder. 


SPEED OF 

PISTON IN FEET PER MINUTE. 


240 

300 

350 

400 

450 

500 

550 

600 

Inches. 

23 

3-021 

3-776 

4*405 

5-035 

5-664 

6-294 

6-923 

7-552 

24 

3-289 

4-111 

4-797 

5-482 

6-167 

6*853 

7-538 

8*223 

25 

3*569 

4-461 

5-105 

5-948 

6-692 

7*436 

8-179 

8-923 

26 

3-861 

4-826 

5-630 

6*435 

7*239 

8-044 

8-848 

9-652 

27 

4-159 

5-199 

6-066 

6-932 

7-799 

8-666 

9-532 

10-399 

28 

4-477 

5*596 

6-529 

7-462 

8-395 

9*328 

10-261 

11-193 

29 

4*805 

6-006 

7-007 

8-008 

9-009 

10-01 

11-011 

12-012 

30 

5-141 

6-426 

7-497 

8-568 

9-639 

10-71 

11-781 

12-852 

31 

5-486 

6 865 

8-001 

9-144 

10-287 

11-43 

12-573 

13-716 

32 

5-846 

7-308 

8-526 

9*744 

10-962 

12-18 

13-398 

14-616 

33 

6-216 

7-770 

9'065 

10-360 

11-655 

12-959 

14-245 

15‘54 

34 

6*59 

8*238 

9-611 

10-984 

12-357 

13-73 

15-103 

16-476 

35 

6-993 

8-742 

10-199 

11-656 

13*113 

14-57 

16-027 

17-484 

36 

7-401 

9-252 

10-794 

12-336 

13-878 

15*42 

16-962 

18-504 

37 

7-819 

9-774 

11-403 

13-032 

14-861 

16-29 

17-919 

19-548 

38 

8-246 

10-308 

12-026 

13-744 

15-462 

17-18 

18-898 

20-616 

39 

8-648 

10-86 

12-67 

14-48 

16-29 

18-1 

19-91 

21-62 

40 

9-139 

11-424 

13-328 

15-232 

17-136 

19-04 

20-944 

22'848 

41 

9-604 

12-006 

14-007 

16-008 

18-009 

20*00 

22*011 

24-012 

42 

10-065 

12-594 

14-693 

16-792 

18-901 

20-99 

23-089 

25-188 

43 

10-56 

13*20 

15-4 

17-6 

19-8 

22-0 

24-2 

26-4 

44 

11-046 

13-818 

16*121 

18-424 

20-727 

23-03 

25-333 

27-636 

45 

11-563 

14*454 

16-863 

19-272 

21-681 

24-09 

26-399 

28-908 

46 

12-086 

15-128 

17-626 

20-144 

22-662 

25'18 

27*698 

30*216 

47 

12*614 

15-768 

18-396 

21-024 

23-652 

26-28 

28*908 

31-536 

48 

12-846 

16-446 

19*187 

21-928 

24-669 

27*41 

30*151 

32-152 

49 

12-913 

17*142 

19-999 

22-856 

25-713 

28-57 

31*427 

34-284 

50 

14-28 

17-85 

20-825 

23-8 

26-775 

29'75 

32-725 

35-7 

51 

14-832 

18-54 

21 -665 

24-76 

27*855 

30-95 

34-045 

37-08 

52 

15-437 

19-296 

22*512 

25*728 

28-944 

32*16 

35-376 

38-592 

53 

16-041 

20*052 

23-394 

26*736 

30*078 

33-42 

36*762 

40-104 

54 

16-656 

20-82 

24-29 

27-76 

31-23 

34-7 

38-17 

41-64 

55 

17*275 

21-594 

25-193 

28-792 

32-391 

35-99 

39-589 

43*188 

56 

17-909 

22-386 

26*117 

29-848 

33-579 

37-31 

41-041 

44-772 

57 

18-557 

23-196 

27-062 

30-928 

34-794 

38-66 

42-526 

46-392 

58 

19-214 

24-018 

28-021 

32-024 

36-027 

40*03 

44-033 

48-036 

59 

19*902 

24*852 

28*994 

33-136 

37-278 

41-42 

45-562 

49-704 

60 

20-558 

25-698 

29-981 

34-264 

38*547 

42-83 

47-113 

51-396 











































172 


THE ENGINEER’S HANDY-BOOK. 


V 


H 

d 

ffl 

◄ 

Eh 


w 




o 

o 

»o 

o 

o 

o 

CM 

CO 

o 

rH 

LO 

rH 

© 

© 

rH 

co 

Pi 



lO 

CO 

LO 

o 

CM 

CM 

LO 

o 

X 

CO 

rH 

© 

b— 

X 

LO 

r 

co 

CM 

H 

W 



o 

tH 

1- 

LO 

Hb 

CO 

CO 

CM 

CM 

CM 

tH 

rH 

rH 

rH 

rH 

rH 

rH 

W 

Pi 




o 

o 

o 

oo 

o 

t-H 

LO 

b- 

-b 

iO 

© 

b- 

X 

X 


© 



3 

CO 

CM 

oo 

t-H 

o 

Hb 

05 

X 

CM 

O 

co 

b- 

LO 

r 

CO 

CM 

CM 

£ 



o 

X 

LO 

H 1 

CO 

CM 

CM 

CM 

CM 

1—( 

rH 

rH 

rH 

rn 

tH 

rH 

M 



rH 
















C/3 

a 



o 

o 

o 

o 

nb 

o 

-b 

o 

CO 

CM 

Hb 

© 

CO 

r— 

CO 

© 

co 

w 



CM 

CO 

-b 

00 

CO 

CM 

b- 

^b 

t-H 

05 

l— 

X 

~b 

X 

CM 

CM 

t-H 

w 

Pi 



CO 

05 

X 

~b 

CO 

X 

CM 

CM 

CM 

rH 

rH 

rH 

rH 

rH 

rH 

rH 

rH 

co 



o 

o 

o 

o 

o 

o 

b— 

LO 

O 

o 

r 

© 

co 

CO 

© 

CM 

X 




o 

o 

o 

LO 

X 

o 

X 

CM 

o 

CO 

X 

LO 

CO 

CM 

CM 

rH 

© 

o 

£H 



CO 

05 

X 

Hb 

CO 

CO 

CM 

CM 

CM 

rH 

rH 

rH 

rH 

rH 

rH 

rH 

rH 

03 

Hi 


H 

H 

o 

o 

o 

LO 

00 

o 

CO 


CO 

nb 

CO 

LO 

■nb 

rb 

X 

© 

CM 

Pi 


05 

b- 

OO 

CO 

^b 

05 

^b 

r-H 

05 

t- 

LO 

nb 

CO 

CM 

rH 

© 

© 

H 


P 

CM 

oo 

LO 

Hb 

CO 

CM 

CM 

CM 

rH 

t-H 

rH 

T—I 

rH 

rH 

rH 

rH 

rH 

fc 

W 

Pi 

w 

Pi 


HH 

s 

o 

o 

o 

o 

X 

o 

O 

o 

i- 

co 

CO 

© 

© 

© 

CM 

LO 

© 


a 

CO 

■Hf 

X 

CM 

X 

CO 

-b 

rH 

OO 

X 

LO 

^b 

CM 

CM 

rH 

© 

© 


CM 

CO 

LO 

Hb 

CO 

CM 

CM 

cm 

rH 

rH 

rH 

rH 

rH 

rH 

t-H 

rH 





















Pi 


£h 

o 

o 

o 

LO 

”b 

O 

t-H 

CM 

o 

CM 

L— 

LO 

iO 

X 

oo 

rH 

LO 

M 


a 


t-H 

nb 

o 

CM 

1- 

co 

o 

CO 

X 


CO 

CM 

rH 

© 

© 

© 

(H 


-3 

CM 

OO 

LO 

^b 

CO 

CM 

CM 

CM 

rH 

r-H 

rH 

rH 

rH 

rH 

rH 

rH 


« 


z 

o 

O 

o 

o 

CM 

O 

CO 

»o 

CO 

X 

CM 

© 

© 

rH 

r 

L- 

CM 

Fri 



CO 

CO 

CM 

05 

t-H 

X 

CM 

05 

b— 

LO 


CO 

CM 

rH 

© 

© 

© 



z 

CM 

b— 

LO 

CO 

X 

CM 

CM 

r-H 

1—1 

T—H 

rH 

rH 

rH 

rH 

rH 



03 


o 



















H 


















£ 


22 

o 

o 

o 

LO 

o 

o 

~b 

t- 

X 

o 

X 

LO 

LO 

b- 

© 


00 

o 


a 

LO 

LO 

o 

1- 

o 

LO 

t-H 

CO 

X 

X 

CO 

CM 

rH 


© 

© 

CO 

HH 

H 

W 

a 

CM 

b— 

X 

CO 

CO 

CM 

cm 

t-H 

t-H 

1—1 

rH 

T—1 

rH 

rH 

rH 



p 


o 


















t-3 

& 


o 

o 

o 

o 

00 

o 

X 

o 

o 

-b 

rH 

© 

rH 

co 

X 

© 

LO 

O 


w 

w 


CM 

CO 

X 

00 

'Hf 

o 

OO 

X 

rb 

CO 

CM 

rH 

© 

© 

© 

CO 

t> 


CM 

t- 

-b 

CO 

CM 

CM 

CM 

r-H 

t-H 

rH 

rH 

H 

rH 

rH 




w 

« 


0, 



















ai 

O 

o 

o 

LO 

X 

O 

1- 

CM 

co 

OO 

LO 

LO 

X 

OO 

CM 

b- 

rH 

Pi 

o 



CO 

05 

X 

— b 

t— 

co 

05 

b- 

LO 

CO 

CM 

rH 

© 

© 

© 

oo 

OO 



CM 

CO 

Hb 

CO 

CM 

CM 

r-H 

r-H 

rH 

rH 

tH 

rH 

rH 




pH 



LO 

LO 

o 

t- 

O 

LO 

co 

05 

o 

LO 

CO 

CM 

r 

X 

© 

Hb 

© 

w 



CM 

1^ 

LO 

CO 

b^ 

CM 

05 

X 

X 

CO 

CM 

rH 

© 

© 

© 

oo 

It- 

P3 



CM 

CO 

-b 

CO 

CM 

CM 

t-H 

rH 

rH 

rH 

rH 

tH 

rH 





<i 
£> 



O 

o 

o 

o 

r 

O 

oo 

LO 

t>- 

CM 

© 

© 

rH 

•rb 

00 

CM 

CO 




CM 

CO 

-b 

CO 

X 

CM 

oo 

X 

Tf 

CO 

CM 

rH 

© 

© 

00 

CO 

b— 



CM 

CO 

Hb 

oo 

CM 

CM 

t-H 

rH 

t-H 

rH 

rH 

rH 

rH 



ft 





O 

o 

o 

LO 

CM 

O 

o 

b- 

o 

X 

r 

LO 

b'- 

© 

r 

© 

r 

■< 



t— H 

co 

CM 

t-H 

LO 

t-H 

GO 

iO 

r 

CM 

rH 

© 

© 

© 

OO 

L— 

b- 

P3 



OJ 

CO 

Hb 

CO 

CM 

cm 

r-H 

t-H 

rH 

rH 

rH 

rH 


W 



o 

>o 

o 

o 

O 

o 

o 

o 

co 

o 

© 

© 

CM 

X 

© 

tO 

o 

o 

PS 

H 





o 

o 

-+ 1 

o 


X 

CO 

CM 

© 

© 

© 

OO 

OO 

t>- 




Pi CM 

X X 

-b 

co 

CM 

CM 

t-H 

— 1 


rn 

rH 

rH 



co 

Ei 

O 

tri 

i-i 

H 

£jJ 



w 

• 

*-H 
• f-H 

v* 

*# 

v# 






s# 


N« 

N# 


v# 

•<* 


s* 

># 

8 

w 



a 

o 

CM 

co 

Tb 

LO 

X 

b— 

oo 

05 

© 

rH 

T—H 

rH 

© 

rH 

CM 

CO 

^b 

LO 

h? 



H 












S* 

v* 

N# 

V* 


0 



cc 












N# 





fc 

HH 














t-H 

rH 

rH 

rH 

rH 

l—l 

r- 

o 

X 

CO 























































THE ENGINEER’S HANDY-BOOK 


173 


P3 

W 

Ph 

H 

W 

w 

p 

£ 


co 

Q 

W 

H 

P 

03 

O 

H 

02 


H 

W 

« 

w 

Cm 

fM 


H 

i-! 

ffl 

<! 


tf 

O 

Pm 

02 

O 

M 

H 

C3 

P 

O 

t> 

W 

tf 

Cm 

O 

« 

W 

« 

S 

P 

o 

£ 

w 

« 

o 

p$ 

H 

co 

P 

O 

W 

H 

O 

fc 

w 

p 

o 

H 

► 

o 


w 

H 

p 

s? 


02 



o 

CD 

id 

CD 


GO 

O 


GO 

■'f 

© 

L— 

-t 

rH 

© 


D 


iD 

rH 

o 

05 

GO 

t'- 


CD 

D 

D 

ID 


''t 1 

-fr 1 

CO 

CO 

CO 


CO 

rH 

rH 
















o 

CO 

o 

CO 

ID 

CD 

OO 

02 

CD 

02 

GO 

D 

02 

© 

GO 

CD 

H* 



rH 

o 

05 

00 

L- 

CD 

CD 

iD 

D 



'■f 


CO 

CO 

CO 


CO 

t-H 

rH 
















o 

CD 

CD 

GO 

o 

02 


OO 

CO 

© 

CD 

CO 

© 

GO 

»D 

CO 

02 



O 

05 

oo 

00 

L— 

CD 

iD 

iD 

LO 




co 

CO 

CO 

co 


CO 

T H 

















o 

O 

o 

Ol 

ID 

CD 

© 

ID 

© 

CD 

CO 

© 

GO 

D 

CO 

rH 

© 


o 

O 

05 

00 

l" 

CD 

CD 

iD 

LO 




CO 

CO 

CO 

CO 

CO 


CO 

r-H 
















a 

290 

t- 


05 

02 


GO 

CO 

OO 

"'■f 

rH 

© 

CD 

T*H 

02 

© 

© 

H 

D 

© 

GO 

L— 

t- 

CD 

D 

ID 




CO 

CO 

CO 

CO 

CO 

02 

*—i 

3 

280 

co 


CD 

o 

02 

CD 

t-H 

t" 

CO 

© 

t'- 

>D 

CO 

rH 

© 

GO 

a 

a 

05 

GO 

t— 

l- 

CD 

»D 

iD 




CO 

CO 

CO 

CO 

02 

02 

H 

o 

o 

rH 


h- 

© 


© 

LO 

rH 

GO 

CD 


02 

© 

GO 

I- 

a 

a 

02 

05 

GO 

L— 

CD 

CD 

ID 




CO 

CO 

CO 

CO 

CO 

02 

02 

z 

>H 

O 

CO 

02 

CD 

00 

rH 

lO 

00 

02 

t— 

CO 

© 

t- 


02 

© 

© 


CD 

S5 

O 

00 


L- 

CD 

iD 

iD 




CO 

CO 

CO 

CO 

02 

02 

02 

H 

m 

HH 

o 

CO 

ID 

00 

co 

*D 

© 

ID 

02 

OO 

CD 

CO 

rH 

© 

GO 

CD 

ID 

rH 

a 

LTD 

02 

GO 

t— 

CD 

CD 

»D 

>D 



CO 

CO 

CO 

CO 

02 

02 

02 

02 

o 


















a 

240 

o 

02 

CD 

O 

CO 

GO 

CO 

© 


rtn 

02 

© 

GO 

1- 

ID 


a 

a 

a 

GO 

L— 

CD 

'CD 

iD 


■H 


CO 

CO 

CO 

CO 

02 

02 

02 

02 

CG 

o 

CD 

o 

CO 

L— 

rH 

CD 

02 

GO 

LO 

CO 

rH 

© 

t- 

CD 


CO 


CO 

02 

L— 

b- 

CD 

iD 

»D 



CO 

CO 

CO 

CO 

02 

02 

02 

02 

02 


lO 

02 

02 

lO 

GO 


CD 

© 

D 

rH 


^ e 02 

© 

GO 

CD 

iD 

CO 

02 


I- 

CD 

CD 

lO 

D 



CO 

OO ®00 

CO 

02 

02 

02 

02 

02 


O 

02 

02 

CO 

CD 

o 

iD 

05 


© 

CD 

CO 

rH 

© 


ID 


CO 

02 


L— 

CD 

CD 

iD 



TP 

CO 

CO 

CO 

02 

02 

02 

02 

02 

02 


O 

o 

CO 

t'- 

02 

t- 

02 

GO 

LD 

02 

© 

CO 

CD 


CO 

02 

rH 


H 

02 

£— 

CD 

iD 

ID 



co 

CO 

CO 

CO 

02 

02 

02 

02 

02 

02 


© 


o 

id 

O 


© 

CD 

CO 

rH 

© 

f- 

iD 

CO 

02 

rH 

© 


4-5 ^ 

p 02 

<D 

CD 

ID 

ID 



CO 

CO 

CO 

02 

02 

02 

02 

02 

02 

02 



• 

<r 






V* 

Vp 


vp 

vp 

VP 

vp 

vp 


vp 


• 

• pH 


v« 

vp 

V# 

v» 

v* 

V* 


vp 


** 

VP 





a 

a 

CD 

GO 

o 

O 

CO 

CD 

© 

© 

CO 

© 

© 

© 

CO 

CD 

© 

© 


o 



rH 















OS 

H 

02 

d 

vp 

V# 

V* 

Vp 

vp 

v* 

Vp 

VP 

vp 

vp 

VP 

VP 

VP 

VP 

vp 

vp 

VP 

vp 

vp 

VP 

vp 

vp 

vp 

vp 

vp 

vp 

>p 



rH 

rH 

t-H 

02 

02 

02 

02 

CO 

CO 

CO 

CO 


Tt< 



D 


15* 



































174 


THE ENGINEER’S HANDY-BOOK. 


H 

i-l 

ffl 

< 

Eh 


a 

w 

Ph 

W 

w 

pH 


02 

Q 

PS 

W 

Ph 

co 

Sz; 

O 

H 

03 

M 

Ph 

H 

W 

Ph 

P 

Ph 

Ph 


PS 

O 

Ph 

co 

>5 

O 

HH 

H 

P 

P 

O 

t> 

W 

Ph 

Ph 

O 

PS 

a 

pp 

S 

P 

fc 

p 

s 

<s 

ps 

W 

o 

PS 

H 

co 

Ph 

O 

W 

H 

O 

Sc 

W 

hJ 

O 

t-i 

£ 

o 

W 

CO 


W 

H 

& 

6 



o 

CO 

o 

CO 

LO 

rH 

o 

rH 

CO 

co 

rH 

co 

04 

QO 

LO 

CO 

o 


o 

CO 

LO 

CO 

04 

H 

o 

05 

QO 

tH 

Ih 

co 

CO 

LO 

LO 

LO 

LO 


lO 

rH 

rH 

rH 

rH 

rH 

rH 












o 

CO 

ih 

CO 

04 

CO 

QO 

05 

rH 

LO 

o 

LO 

t-H 

IH 


04 

05 


05 

CO 


CO 

04 

o 

05 

CO 

QO 

tH 

Ih 

CO 

CO 

LO 

LO 

LO 

r 1 



rH 

rH 

rH 

rH 

rH 













o 

05 


rH 

o 

CO 

CO 

t— 

O 

"T 1 

CO 


o 

CO 

CO 

rH 

QO 


OO 

lO 

''tf 

CO 

04 

o 

05 

GO 

QO 

tH 

CO 

CO 

CO 

LO 

LO 

lO 




rH 

rH 

rH 

TH 

rH 













o 

CO 

rH 

OO 

tH 

-f 

-r 

LO 

00 

04 

r— 

04 

OO 

LO 

04 

05 

1^ 


r— 

LO 


04 

rH 

o 

05 

QO 

tH 

tH 

CO 

CO 

LO 

LO 

LO 

■"f 




rH 

rH 

rH 

rH 

rH 












y 

o 

CO 

QO 

LO 

Hf 

04 

04 

CO 

CO 

o 

LO 

rH 

t'- 


t-H 

QO 

CO 

H 

CO 

LO 

CO 

04 

tH 

o 

05 

OO 

tH 

tH 

CO 

CO 

LO 

LO 

LO 



D 

ft 


rH 

rH 

rH 

rH 

rH 












NH 

S 

o 

o 

LO 

04 

04 

o 

o 

rH 

LO 

05 


o 

CO 

CO 

o 

tH 

LO 


lO 

LO 

CO 

04 

rH 

o 

05 

GO 

tH 

CO 

CO 

CO 

LO 

LO 

LO 



a 

"Cf 

rH 

rH 

tH 

rH 

rH 












H 

o 

CO 

04 

o 

o 

t- 

QO 

o 

CO 

I- 

04 

00 

LO 

rH 

OO 

CO 





CO 

04 

rH 

05 

OO 

QO 

tH 

CO 

CO 

LO 

LO 

LO 


Tjl 

''f 

y 

y 


r-H 

rH 

tH 

rH 













A 

o 

CO 

05 

tH 

tH 

LO 

CO 

QO 

rH 

CO 

rH 

h- 

CO 

o 

tH 

LO 

CO 

M 

CO 


04 

rH 

o 

05 

QO 

tH 

tH 

CO 

CO 

LO 

LO 

LO 



"T 1 

A 

O 


rH 

rH 

tH 

rH 













H 

OJ 

o 

o 

co 

HP 

LO 

CO 


CO 

o 


o 

CO 

04 

05 

CO 

"T 1 

04 

Ph 

<M 

•'f 

Ol 

rH 

o 

05 

QO 

tH 

tH 

CO 

CO 

LO 

LO 


-sf 



y 


rH 

rH 

rH 

rH 













o 

Q 

o 

CO 

co 

04 

04 

rH 

04 


OO 

CO 

CO 


rH 

OO 

LO 

CO 

rH 

a 

rH 

CO 

04 

rH 

O 

05 

CO 

tH 

CO 

CO 

LO 

LO 

LO 

'"f 


''f 


a 

Ph 


rH 

rH 

rH 

rH 













co 

O 

CO 

o 

05 

o 

05 

o 

04 

CO 

rH 

tH 

CO 

o 

tH 


04 

o 


o 

CO 

04 

o 

o 

OO 

00 

tH 

CO 

CO 

LO 

LO 

LO 



'Cf 

'Pf 



rH 

rH 

rH 

rH 














o 

o 

ih 

Hh 

IH 

CO 

CO 

rH 

LO 

o 

LO 

04 

QO 

LO 

CO 

rH 

05 


05 

CO 

rH 

o 

05 

GO 

tH 

tH 

CO 

CO 

LO 

LO 


''f 



CO 


CO 

rH 

rH 

rH 















o 

CO 


co 

LO 


CO 

o 

CO 

CO 


o 

tH 

rfi 

04 

.o 

GO 


CO 

04 

rH 

o 

05 

CO 

tH 

tH 

CO 

LO 

LO 

LO 





CO 


CO 

rH 

tH 

rH 















o 

co 

rH 

tH 

04 

04 


tH 

rH 

CO 

04 

05 

CO 

CO 

rH 

05 

tH 


ih 

04 

rH 

o 

05 

00 

tH 

CO 

CO 

LO 

LO 

TJH 




CO 

CO 


CO 

rH 

rH 

rH 















• O 

>o 

OO 

co 

o 

o 

04 

LO 

o 

LO 

rH 

00 

TJH 

04 

o 

co 

CO 


£<c© 

$04 

o 

05 

05 

CO 

tH 

CO 

CO 

LO 

LO 

"'t 1 




CO 

CO 


^co 

PSr-l 

t-H 

















• 

fl 





- 








v* 

v* 

Va 


w 

• pH 








X 


V* 



N* 


N# 


a 

CO 

CO 

o 

O 

CO 

CO 

05 

o 

CO 

CO 

05 

o 

CO 

CO 

05 

o 


o 

a 

• 


H 















H 

CO 

< 4h 







V* 

v2 


V# 

V# 

vJ 

vJ 

N# 

>» 



rH 

rH 

tH 

04 

04 

04 

04 

CO 

co 

CO 

CO 





LO 







































THE ENGINEER^ HANDY-BOOK. 


175 


E 


v: 


r\\ 


£- 


E 


C- 


(r 


<L 



]=, 


Piston, Connecting-Rod, and Crank Connections. 

An idea very generally prevails among engineers that the 
crank of a steam-engine travels 
faster at one part of the stroke 
than at the other. This is evident¬ 
ly a mistake. The crank travels 
at a uniform speed throughout its 
revolution, but the piston travels 
farther to make one-half its stroke 
than the other- If the connecting- 
rod were indefinitely long, or a 
slotted yoke were substituted for it, 
the movement of the piston would 
be determined by the crank alone; 
its points of mid-travel would cor¬ 
respond exactly with the corre¬ 
sponding points in the travel of the 
crank, and the piston would occupy 
the same position at the first and 
last half of each stroke. But in 
consequence of the distorting action 
of the connecting-rod, the piston 
travels farther during the half of 
each stroke farthest from the crank, 
and consequently, when the crank 
is at its point of mid-travel, that is, 
when it is perpendicular to the 
axial line of the cylinder, the piston 
is nearer the crank than its point 
of mid-travel by an amount which 
varies inversely with the length of 
the connecting-rod, and which is 
equal to the difference between the 
base and the. hypothenuse of the 
right-angled triangle formed by the 













































176 


THE ENGINEER’S HANDY-BOOK. 


connecting-rod, crank, and the included portion of the line. Now 
the square of the hypotheuuse of a right-angled triangle is equal 
to the sum of the squares of the other two sides. 

The crank of a steam-engine moves six times as tar while the 
piston is travelling the first inch of the stroke as while it is mak¬ 
ing the middle inch ; a little over twice as far while the piston is 
moving the second inch; a trifle over 14 times as far while the 
piston moves the third inch; and less than 1^ times as far while 
the piston is making the fourth inch. The crank also travels less 
when the piston is making the last inch of the stroke than it does 
while it is making the first. Another fact, not generally recog¬ 
nized by inexperienced persons, is that the crank of a steam- 
engine at certain points travels a considerable distance, while the 
cross-head has a motion which is hardly perceptible. 

Rule for finding the distance the piston is ahead of a central 
position in the cylinder on the forward stroke, and also the dis¬ 
tance which it lags behind on the backward stroke. 


Subtract the square of the length of the crank from the square 
of the length of the connecting-rod; find the square root of the 
difference or renminder, and subtract it from the length of the 
connecting-rod. The remainder will be the variation of the piston 
from a central position when the crank is at right angles to the 
centre line of the engine. 

Example. — Length of crank, 12 in. 

Length of connecting-rod, 72 “ 

Then 72 2 = 5184 in. 

12 2 — 144 “ 


Difference — 5040 “ 


^5040 = 70-992 in.; and 





72 

70-992 


1°008, which is the variation in 
inches. 




THE ENGINEER'S HANDY-ROOK. 


177 


The Reynolds Corliss Engine. 

The cuts on pacjos 178,179, represent the front and back views 
of the Reynolds Corliss Engine. It will be observed that the 
frame is of the girder pattern, the front end of which is faced up 
to receive the cylinder and slides, while the back end contains 
the pillow-block bearing; the whole being supported by three pair 
of legs, which insures rigidity and prevents the possibility of 
springing, in case the engine should be run at a high rate of 
speed or loaded beyond its rated capacity. The cross-head has 
its support on the slides, directly opposite the centre of the cross¬ 
head pin, thus avoiding the springing and final breaking of piston- 
rods, as is often the case where the support is carried back of the 
centre of the cross-head, as is done in most engines of this type. 
It is provided with convenient mechanical arrangements for easy 
and accurate adjustment in case of wear. 

The valves are of such construction that they have double the 
wearing surface ordinarily found in engines of this type. This 
obviates the rapid wear of the seats, which must occur where the 
wearing surfaces are small; while, in consequence of the peculiar 
construction of the valve-gear of these engines, they can be run 
at any desired speed. The valves open with perfect regularity 
and close instantaneously, which is a feature of great importance 
in itself, especially in flouring-mill3, as it admits of the line-shafting 
being coupled directly to the engine-shaft, thus avoiding the use 
of expensive counter-gearing, and still giving the fly-wheel suffi¬ 
cient motion to properly “ lead ” the stone and avoid “ backlash." 
No springs are required on either steam- or exhaust-valves. The 
steel catches used for opening and liberating the steam-valves are 
so constructed and arranged as to give eight wearing faces on each 
piece; while by unhooking the eccentric-rod, all the valves can 
be easily moved and the engine worked by hand, which prevents 
the liability of its catching on the centre, which is a source of 
annoyance, especially in the case of large engines. The liberating 
portion of the valve-gear is claimed to be an improvement on any 

M 


178 


THE ENGINEER’S II ANDY-BOOK 



Front View of the Reynolds Corliss Engine. 




















































































































































































































































































































































































































































































































































































































180 


THE ENGINEER’S HANDY-BOOK. 


other arrangement employed on any Corliss engine in use at the 
present day. 

Some of the most important features of the Reynolds Corliss 
Engine are that they are stronger and heavier than most engines 
of that class; that the valves are under the complete control of 
the governor, which is very powerful and sensitive, thus insuring 
uniformity in speed, which is a feature of great importance for 
milling and most other manufacturing purposes; that the valve- 
gear is simple and conveniently arranged for accurate adjustment; 
that the fly-wheel is turned on the face and sides and accurately 
balanced; that the wearing surfaces, whether revolving or rub¬ 
bing, are ample, which prevents the possibility of rapid wear and 
the expense of repairs ; and that the cross-head pin, crank-pin, and 
piston-rod are made of steel, and the crank-shafts of the best ham¬ 
mered iron. 

The Reynolds Corliss engines are in very general use, and have 
a well-earned reputation for durability, efficiency, and economy. 
The condenser and air-pump are new in design, simple, and effi¬ 
cient ; in fact, the whole design and arrangement of these engines 
show them to be the result of mature mechanical deliberation. 
They are manufactured, both condensing and non-condensing, 
simple and compound, of any size and power, to meet the re¬ 
quirements of purchasers, by Edward P. Allis & Co., Milwau¬ 
kee, Wis. 

Steam- and Exhaust-Pipes. 

The diameter of the steam-pipe varies with leading engine 
builders between l and J the diameter of the cylinder, the exhaust- 
pipes being from about 30 to 50 per cent, larger. Some builders 
make them little, if any, larger; but too small steam- and exhaust- 
pipes are a prevailing vice amongst small builders, especially 
those in country districts, who do not use an indicator to determine 
their proportions. The proper diameter for steam- and exhaust- 
pipes may be found by multiplying the diameter of the piston in 
inches by its speed in feet per minute, and dividing the product 



THE ENGINEER’S HANDY-BOOK. 181 

by 1440 for steam- and 1140 for exhaust-pipes ; the quotient will 
be the diameter of the pipes in inches. For short and direct 
pipes, however, the divisor may be increased to 2000 for steam- 
and 1440 for exhaust-pipes. These latter divisors will give pro¬ 
portions a trifle larger than the average, especially for exhaust. 

Rock-Shafts. 

Some engine builders make the diameter of the rock-shaft 1 

the diameter of the crank-shaft; if subjected to torsion, it should 
he |, and in some cases 5, the diameter. The torsion on a shaft is 
in proportion to the length of the arm to which the valve is at¬ 
tached. About 10 times the area of the slide-valve in square 
inches will nearly equal the force in pounds required to move it 
under 100 pounds steam pressure, though, when dry or starting, it 
may amount to 12 times or more. The diameter of a rock-shaft 
may he found by the following rule. Multiply the maximum re¬ 
sistance in pounds by the length of the arm which divides the 
valve, and divide the product by 128; the cube root of the quo¬ 
tient will be the diameter of the shaft in inches. The size thus 
found will answer for ordinary wrought-iron shafts, and will resist 
greater strain than the above rule provides for. The rocker and 
rock-shaft are being fast superseded by the guide-block. 

Cross-Head Bearings. 

The area of the wearing surface of a cross-head (that is to 
say, 4 the total, above and below) should not be less than -J the 
area of the piston, nor ever exceed ^ °f it. Many steam-engine 
builders make the length of the cross-head bearings f the diameter 
of the cylinder, and their width of the same, which appears to 
be a good proportion, and may he illustrated as follows: f of a 
12 in. cylinder is 8 inches in length, and 2 5 5 is 2^ inches in width, 
which gives 20 sq. inches for each shoe, or 40 for both, which is a 
good proportion ; but it should be slightly greater in the case of 
10 


182 the engineer’s itandy-book. 

short connected engines running at a high speed. The cross-head 
gibs are generally termed shoes, and the grooves in which they 
move are called V’s. 

'y • ' 

Talve-Rods. 

The diameter of valve-rods varies for moderate sized engines 
from y 1 ^ to yrj the diameter of the cylinder. Their diameter in 
any case should be proportioned to the size of the valve, whether 
it is balanced or not. If T y the area of the valve be considered 
as a piston of such area, | its diameter will bear about the same 
relation to its maximum strain as piston-rods do; but valve-rods 
are generally made somewhat larger than such a rule would give, 
because they are not so well protected against side strains as pis¬ 
ton-rods. Probably, since the area of a piston-rod should be from 

to the area of the piston, according to its length and ma¬ 
terial (steel may be smallest), a valve-rod should be about from 
3 in *° 3 in the unbalanced area of the valve for high-pressure 
engines. 

The Eccentric. 

The eccentric. — An eccentric is substantially a crank, with its 
pin enlarged in diameter so as to inclose the shaft on which it is 
placed within its periphery. It gives exactly the same motion 
that would be obtained from an ordinary crank of equal throw. 
The eccentric is sometimes called a cam, which is erroneous, as the 
latter is always used to obtain a motion different from what can 
be obtained from a crank. The term “ cam,” when used without 
qualification, is indefinite, and conveys no impression of its precise 
form or functions. It is a mechanical element of such a form 
that a solid body held against, but not revolving with, the pe¬ 
riphery of contact may have an intermittent, alternating motion. 

Fore eccentric. — A “term ” applied to the eccentric, which is 
connected by its rod to the upper part of the link, to move the 
valve for the forward motion; but the reason that the forward 
motion is derived from the upper end of the link arises from 



THE ENGINEER’S HANDY-BOOK. 


183 


convenience, and not from necessity. The reverse conditions could 
be introduced very easily. 

Back eccentric. — The eccentric connected to the lower end of 
the link by which the valves are adjusted for the backward motion. 

Throw of the eccentric. — The “term” throw of the eccentric 
is understood to be the same as the travel it imparts to the valve, 
and which is understood to be equal to the width of both steam- 
ports with the lap added. 

Angular advance of the eccentric means the angle at which it 
stands in advance of that which it would occupy if the valve 
were in the centre of its travel, and the crank at its centre. 


Tlie Crank. 


90 °; 


The generally prevalent idea among mechanics that there is an 
actual loss of power in the use of the crank, has stimulated in¬ 
ventors to substitute for it a device that would utilize all the power 
exerted against the piston 
without loss. As a result, the 
U. S. Patent-Office, as well as 
those of the different coun¬ 
tries of Europe, are crowded 
with arrangements intended 
to supersede the crank ; the 
most popular, and conse-180°\ 
quently the most frequently 
resorted to, being the rotary 
engine, in which the effective 
force of the steam would be 
constant, while in the case of 
the crank it is intermittent ; 
but, so far, no rotary arrangement has ever been able to compete, 
in point of economy, with the reciprocating motion of the crank. 

Strictly speaking, there is no loss of power in the use of the 
crank, as, while there is a great variation in the power a given 



270 ° 





184 


THE ENGINEER’S HANDY-BOOK. 


pressure of steam can exert at different points of the stroke, it is 
known that when the power is least the consumption of steam is 
least. Suppose an engine has 2-feet stroke, the piston would travel 
4 feet tor each revolution ; during each stroke the effective length 
of the crank varies from 0 to 1 foot; its average effective length 
would be equal to the radius of a circle whose circumference was 
4 feet, or 7‘68 inches. The power of the engine would be the 
same as if it acted on a constant crank of 7'68 inches, and the 
displacement, and consequently the consumption of steam, would 
be the same as before. 

If the piston acted on a constant or average crank of 12 inches 
in length, it must travel a distance equal to the circumference of 
a 24-inch circle, or 63| inches. Though such an engine would 
have proportionately more power at the same number of revolu¬ 
tions, it would consume proportionately more steam. The power 
of a crank is greatest for early cut-offs at the point at which the 
valve closes, and for late cut-offs when it stands at right angles 
with the connecting-rod, which point, as may be seen from the 
cut on page 175, is not in the middle of the stroke. 

An examination of the connecting-rod of an engine in motion, 
will show that the two ends pass over different spaces in a given 
time. If, for instance, in one stroke the end of the connecting- 
rod that is attached to the cross-head moves through one foot, the 
end which is attached to the crank-pin, and makes a half revolu¬ 
tion in the same time, passes through 1*5708 feet. Suppose that 
an engine is placed with its crank on the centre, and steam is ad¬ 
mitted ; no motion will be produced, and consequently there will 
be no power developed, and no expenditure of steam; but let the 
piston make a stroke, the power exerted is equal to the force or 
pressure acting on the piston multiplied by the space passed 
through, or it will be 100 foot-pounds, assuming the data previ¬ 
ously given. During the same time the crank-pin has passed 
through a space of 1*5708 feet, and the force or pressure exerted 
has been 63*66 pounds, so that the power exerted during this time, 
or the product of 1.5708 multiplied by 63*66, is 100 foot pounds. 


THE ENGINEER’S HANDY-BOOK. 


185 


The boss of the crank is that part into which the shaft is in¬ 
serted, and which butts against the main-bearing. In common 
pr actice, its width, when of cast-iron, is about twice the diameter 
of the crank-shaft journal, and the width at the pin is generally 
about twice the diameter of the pin. The section of the crank be¬ 
tween the shaft and the pin is termed the web; its area is gener¬ 
ally equal to that of the crank-shaft. When the crank is round, 
it is called a crank-plate, or disc. The only advantage that the 
circular possesses over the ordinary form is that it affords better 
facilities for balancing. 

Crank-Pins. 

Probably no part of the steam-engine more imperatively requires 
perfection in material and workmanship than the crank-pin, if cool, 
noiseless running is considered desirable. Yet it would be safe to 
say that the cranks of most engines are so imperfectly fitted as to be 
out of line with their shafts. The most frequent causes of trouble 
with crank-pins are lack of parallelism between the pin and shaft, 
imperfect material, untrue turning, and inadequate wearing surface. 

It is generally understood that, when a pressure exceeding about 
800 lbs. per square inch is imposed upon a journal, lubrication 
with oil is no longer adequate to prevent destructive wear. In 
the case of crank-pins this limit is frequently approached, and in 
some cases exceeded. Very few engine manufacturers make their 
crank-pins exceed one-fourth the bore of the cylinder in diameter 
and one-third of it in length, the majority being short of this pro¬ 
portion. 

Assuming this proportion, and that the rule for finding the 
effective wearing surface of a journal is to multiply its diameter 
by its length, a little calculation will show that the area of the 
piston exceeds the wearing surface of the pin over 9 T 4 0 times. 
Then suppose the piston to be subjected to a pressure of 85 lbs. per 
square inch, which is not unusual, the pressure on the crank-pin 
will be 85 X 9’4 = 799 lbs. per square inch. If such a pressure 
was constant, it is very probable that no material, perfection of 
16 * 


186 


THE ENGINEER’S HANDY-BOOK. 


workmanship, or lubrication would prevent the heating and speedy 
destruction of the pin and boxes; but in the case of the crank-pin 
such pressures are but momentary, and do not last long enough 
to allow destructive wear to begin. The alternating intervals of 
no pressure assist in the necessary redistribution of the lubricant; 
still, when we multiply the mean pressure on the piston by the 
number of times that its area exceeds that of the pin (ten times, 
in many cases), the wonder will be not that so many pins give 
trouble, but that so many do not. An increase in the dimensions 
of the pin would, it is true, proportionately diminish the pressure 
per square inch ; but the loss of power, by the increased friction 
thus induced, would be equally as objectionable as the evil which 
it was intended to remove. 

The length of a crank-pin should be equal to the horse-power 
of the engine divided by the stroke; the quotient multiplied by 
a coefficient which has been found by experiment to range from 
1*3 to T5. For instance: if a crank-pin is required for an engine 
24" x 48", capable of developing 250 Hp., then 250 -5- 48 X 1*5 
= 7*81, or 7}f in., which is the required length. 

To determine whether a crank-pin is in line with the centre of 
the cylinder or not, put on the connecting-rod and key the box up 
snug on the pin; then disconnect the rod from the wrist of the 
cross-head and move the crank round, and if the rod maintains a 
central line in whatever position the crank may be placed, the 
crank-pin is in line with the centre of the cylinder. This test will 
also serve to prove the correctness of the boring of the pin-boxes. 
If they are not bored exactly at right angles to the centre line of 
the rod, troubles similar to those caused by an untrue pin will 
ensue. Another oversight not generally thought of, and which 
causes much trouble with crank-pins, is that, in planing off the 
stub-ends of the connecting-rod, the machinist, through ignorance 
or inattention, planes more off one side than the other. As a re¬ 
sult, every time the rod changes its position, the box will pinch on 
the crank-pin, and cause undue heating. 


THE ENGINEER’S HANDY-BOOK. 


187 


Crank-Shaft Journals and Main-Bearings. 

The conditions so essential in the manufacture of crank-pins, 
viz., good material, excellent workmanship, and accurate fitting, 
hold good also in the case of crank-shaft journals. Unlike the 
crank-pin, steel is not used in the case of shafts, principally in 
consequence of its extra cost; therefore forged or rolled iron is the 
material most generally employed. Since wrought-iron is never 
found perfectly homogeneous, the difficulties which lie in the way 
of a perfectly true and cylindrical journal are much greater than 
with a steel crank-pin. 

When the initial pressure on the piston is 80 lbs. per sq. inch 
or upwards, the diameter of the crank-shaft bearing should not be 
less than £ the bore of the cylinder; and, in order to prevent 
springing, it should be as near the centre-line as possible. Al¬ 
though it will be impossible to entirely prevent springing, with 
high speed and initial pressure, yet, by this arrangement, the lia¬ 
bility to spring may be very much diminished. The length of the 
crank-shaft journal should not be less than twice its diameter, 
though some engine builders of good repute make them shorter. 
The longer the journal, within reasonable limits, the more durable 
it will be, providing the shaft does not spring, and is always per¬ 
fectly in line with its bearings. But as these conditions cannot 
be always realized for any length of time, it is not advisable to 
attempt any greater length than the foregoing. 

As the pillow-block bearing is not self-adjusting, it is of great 
importance that it should be perfectly true with the line, so that 
the contact of the shaft may be as nearly even as possible through¬ 
out. The most general construction consists of a bottom box, side 
and quarter boxes, adjusted by set-screws, or wedges and a cap; 
but the simple box and cap, parted at an angle of about 30° from 
the perpendicular, with its bolts as short as possible consistent 
with requisite strength, possess the important advantages that they 
do not tighten on the journal when it begins to heat, as is the case 
with many of the ordinary forms in use, and that at that angle 


188 


THE ENGINEER^ IT ANDY-BOOK. 


the compensation, both horizontal and vertical, may be better pro¬ 
vided for. The outer pillow-block bearing being subjected to less 
severe wear, does not require the same care in its proportions and 
finish, but should not, for that reason, be slighted. 

Keys, Gibs, and Straps. 

The key, gib, and strap are the most simple and effective me¬ 
chanical devices which could be employed for securing the con¬ 
necting-rods of steam-engines to the wrist- and crank-pins, and 
taking up the lost motion in the boxes, as they possess sufficient 
strength without extra weight of material, and facilitate quick and 
easy adjustment. There is quite a wide difference of opinion among 
builders in proportioning the keys, gibs, and straps of their en¬ 
gines. Some make the thickness of both straps on the connecting, 
rod 4 the diameter of the crank pin, and their width about | the 
length of the pin ; while others make the width of their straps 
three times their thickness, and the area of the cross-section at the 
mortise equal to the area of the smallest part of the connecting- 
rod ; while others, still, make them equal in strength to the weakest 
point in the piston-rod, which they undoubtedly should be in any 
case. It has been customary, heretofore, to make straps thinner 
at the yoke than at the mortise; but this has been partly aban¬ 
doned, as the amount of material saved was insignificant, while 
the extra work was considerable. The depth of the gib and key 
in a good engine is generally about three times their thickness, 
and the taper at about 1 in ten; though it ranges all the way 
from the latter to 1 in 24, 1 in 15 being about the average. It is 
customary in some instances, as in the case of marine engines, 
locomotives, and other fast-running engines, to pass a bolt, and in 
some cases two, through the stub-end and straps, as a precaution 
against accidents; the holes in the straps being the exact size of 
the bolt, while those in the stub are slotted, for the purpose of 
admitting of adjustment by the key and gib. 


THE ENGINEER^ HANDY-BOOK. 


189 



The Link. 

The link-motion is an arrangement of valve-gear for reversing 
engines and varying the rate of expansion. It consists of two 
eccentrics, with straps and rods. The eccentrics are so placed 
that when one is in the right position for the engine to move for¬ 
ward, the other is in the position for moving backward; and by 
raising or lowering the link, motion will be communicated to the 
valve and the engine will move backward or forward. The re¬ 
sult of this combination is that the link receives a reciprocating 
motion in its centre; since, when one eccentric is moving the end 
of the link in one direction, the other is moving the other end in 
the other direction ; so that the link will have nearly the same 
motion communicated to it as if it were suspended from a pivot 
at its centre. 

The horizontal motion communicated to the link by the joint 
action of the eccentrics, is a minimum at the centre of its length, 
where it is equal to twice the linear advance, and it increases to¬ 
wards the extremities of the various periods of the block in the 
link, or of the link on the block, on the general principle that 
admission varies with the travel of the valve. The nature of the 
motion derived from the link is modified by the positions of the 




















190 


THE ENGINEER’S HANDY-BOOK. 

working centres, and most especially of the centres of suspension 
and connection. The centre of suspension is the most influential 
of all in regulating the admission, and its transition horizontally 
is much more efficacious than a vertical change of place to the 
same extent, inasmuch as the vertical movement of the body of 
the link, with the consequent slip between the link and the block, 
is the least possible when the suspended centre lies in the centre 
line of the link, and increases as the centre is moved laterally. 
The centre line of the link is therefore, in this respect, the most 
favorable location for the suspension, even though it be not always 
practicable for equal admissions. 

The amount of travel communicated to the valve depends upon 
the distance the block is from the centre of the link. By moving 
the link up or down on the block, the travel of the valve will 
either be increased or decreased; and since the travel of the valve 
is the measure of the lap, to reduce the travel is tantamount to 
increasing the lap, and also the lead. Thus the link-motion be¬ 
comes an expedient for regulating the amount of expansion with 
which the engine works. Though it may be claimed by some 
that cutting off* by the link has a tendency to affect the exhaust, 
it does not do so to any injurious extent, as the later opening of 
the exhaust is a positive advantage, as it balances the resistance 
due to the early admission of the steam at the other end, before the 
engine has reached the end of the stroke. It will be seen, for the 
foregoing reasons, that the link is a perfect expansion-gear, as, 
when in full stroke, it is superior, in many respects, to most other 
cut-off devices, since, while the lead is increased as the travel of 
the valve is decreased, or, in other words, as the link is lifted to¬ 
wards the centre, and the supply of steam cut off at an earlier 
point in the stroke, the lead becomes a positive advantage, as it 
serves as a cushion to the piston when its reciprocating motion is 
rapid, as is frequently the case. 

The ease and facility with which the link may be handled is 
another very important feature in its favor. In fact, what could 
we do without it when handling engines, especially large locomo- 


THE ENGINEER^ HANDY-BOOK. 


191 


tives or marine engines, which have of necessity to run backwards 
with the same ease, speed, and facility as they run ahead? The 
link is a splendid mechanical conception, and one of the greatest 
improvements that has ever been made in the locomotive, marine 
engine, or any other class of motors requiring a reversing gear. 

The radius of the link is the distance from the centre of the 
driving-axle, or shaft on which the eccentric is located, to the 
centre of the link; while the link itself is a segment of the circle 
of that diameter. The length may be longer or shorter; but any 
variation from these proportions will give more lead at one end 
than at the other while working steam expansively; but the ra¬ 
dius may be several inches shorter or longer, without materially 
affecting the motion. The vital point in designing a valve link- 
motion is the point of suspension of the link. If it is suspended 
from the centre, it will invariably cut off steam sooner in the 
front stroke than in the back stroke, while working expan¬ 
sively. 

The nearer the block is brought to either end of the link, the 
greater will be the travel of the valve, and the more the steam 
and exhaust will be opened. The term “ full-gear forward ” means 
that the link is dropped to its full extent; while “full-gear back¬ 
ward ” means that the link is lifted to its full extent. When the 
link-block stands directly under the saddle-plate, both ports are 
closed, and neither admission nor exhaust can take place. The 
distance between the block and the end of the link when in full- 
gear is termed the clearance. 

In the Walschaert link-motion, which was used on one or two 

of the small engines at the Centennial Exposition, the mid-gear 
movement was derived directly from the cross-head, while the end, 
or full-gear, movement was derived from a single eccentric, or a 
return crank, from the main crank-pin. The middle of the link 
is stationary, and, of itself, imparts no motion to the valve; but 
between the link and valve is an arrangement for imparting a 
reduced and reversed copy of the piston movement to the valve, 
which movement, being always present, modifies that of the ec- 


192 


THE ENGINEER’S HANDY-BOOK. 


centric at all points, giving it the effect of angular advance, which 
is not given to the eccentric in the case of the ordinary link-mo¬ 
tion. 

Lifting and stationary links. — The lifting-link is raised and 
lowered to effect the changes it is designed to perform ; while in 
the stationary link the block, instead of the link, is shifted. In 
the stationary link but one eccentric is generally used, the throw 
of which corresponds to the middle of the ordinary link ; for this 
reason, more mischief would be caused by any lost motion in the 
eccentric straps or other connections. Moreover, it does not allow 
of ready, independent adjustment of the backward and forward 
motion in full gear. 

Fly-Wlieels. 

The object of the fly-wheel is to equalize the motion whenever 

either the pow r er communicated or the resistance to be overcome 
is variable. In the one case, the fly-wheel may be said to be a 
distributor of power. The complicated impulses, acting on the 
mass in motion, preserve the momenta, without disturbing the 
regularity of movement. The effect of one impulse is so absorbed 
or distributed in the momentum of the wheel, that it may be said 
to have hardly been diminished before the next impulse is re¬ 
ceived. 

In the other case, or where the flv-wheel is used to overcome a 
variable resistance, it may be considered a conservator of power. 
The power having been exerted in getting up the speed, is retained 
in the moving mass, and the whole of the power expended, with the 
exception of that which has been lost through friction and resist¬ 
ance of the air, can be brought to bear at any instant upon the 
resistance to be overcome. When the crank and connecting-rod 
are in one straight line, as they must be twice in each revolution, 
the crank is said to be on its dead-centre, because there the 
force of the piston is dead or ineffective. It is evident that, when 
the crank is at right angles to the connecting-rod, the latter is 
exerting the maximum of power; but when the forward or back- 


THE ENGINEER’S HANDY-BOOK. 


193 


ward dead-centre is reached, the crank would remain there, but 
for the action of the fly-wheel, which, by its accumulated momen¬ 
tum, carries it over the dead-centre. 

Thus, through the momentum of the fly-wheel, no perceptible 
variation occurs in the velocity of the engine ; the unequal le¬ 
verage of the connecting-rod is corrected, and a steady and uni¬ 
form motion produced. The fly-wheel, as before stated, is a 
regulator and reservoir, and not a creator of motion. The ac¬ 
cumulated velocity in the fly-wheel, where the motion is required 
to be excessively equable, should be about six times that of the 
engine when the crank is horizontal. As regularity of motion is 
of much greater importance in some cases than in others, the 
weight and diameter of the fly-wheel must depend on the work 
and the character of the machinery it is intended to drive; so 
that, in proportioning a fly-wheel to a given engine, attention must 
be paid to many particular circumstances rather than to any given 
rule. There are circumstances in which the use of a fly-wheel 
may be dispensed with, as where a pair of engines work side by 
side, whose cranks are at different angles, so that one assists the 
other to pass the centres, or where smoothness of motion is not an 
absolute necessity. 

Rule for finding the proper weight of the fly-wheels of steam- 
engines. 

Divide the constant number 7,000,000 by the square of the 
number of revolutions per minute, and by the diameter of the 
wheel in feet. The quotient will be the number of pounds per 
horse-power required in the rim of the wheel. 

The above rule is correct, so fax as it recognizes the fact that 
the efficacy of a fly-wheel increases with the square of its velocity 
and with its diameter. The constant number is found by taking 
some engine whose fly-wheel is known to be right at a given load, 
dividing its weight by the horse-power developed, and multiplying 
the quotient by the square of the number of revolutions per min¬ 
ute, and by the diameter. When so found, it will give correct 
results for all other engines of the same class doing similar work. 

17 N 


194 


THE ENGINEER’S HANDY-BOOK. 


This constant number must not, however, be regarded as arbi¬ 
trarily fixed. It will give the weight of the wheels near enough 
for automatic cut-off engines. 

The Watertown Automatic Cut-Off Engine. 

The cut on the opposite page represents the Hampson Auto¬ 
matic Cut-Off Engine, the bed plate of which, as will be observed, 
is of the box pattern; the metal in which is so distributed as to 
combine strength, stiffness, and rigidity, without extra weight. 
The steam-cylinder and main pillow-block and guides are at¬ 
tached to the bed-plate in such a manner as to prevent the 
possibility of becoming loose when the engine gets out of line. 
As the steam-chest is the full length of the cylinder, with the 
ports opening directly from it into the clearance, it enhances the 
value of these engines very much, as it obviates the waste induced 
by long steam-ports. 

The valve-gear receives its motion from two eccentrics on the 
main shaft, the one next the pillow-block being connected with 
the main valve, which is an ordinary slide-valve, with this ex¬ 
ception — that the steam, instead of passing in at the ends of it, 



enters through it by means of ports, as shown at C D , Fig. 1. 
H represents the back of the main valve, which is also the seat 







































































































































































































































































The Watertown Automatic Cut-Off Engine. 


195 





































































































196 


THE ENGINEER’S HANDY-BOOK. 

of the cut-off valve, G. F represents the stem of the main valve, 
and B the stem of the cut-off valve, which is continued on through 
the end of the steam-chest, and is held steady when the engine is 
working by means of a horn at A. The reader will notice that 
there is a rack cut in the back of the cut-off, which engages the 
teeth of a small wheel on the valve-stem, and from this device any 
one would soon come to the conclusion that the adjustment of the 
cut-off is accomplished by rolling the valve-stem. This, as a matter 
of course, will raise and lower the cut-off valve by means of the 
rack and pinion, thereby opening the ports. 

The governor, which is very powerful and sensitive, embodies 
some peculiarities of design and construction not common in govern¬ 
ors, inasmuch as the point of suspension, instead of being on the same 
side of the spindle as the ball, is carried over to the opposite side, 
thereby greatly increasing its power and sensitiveness. Directly 
under the governor there is a disc on the valve-stem, with teeth 
cut on the periphery about half the circumference, and these teeth 
engage a rack connected with the governor-spindle. Consequently, 
as the balls of the governor rise and fall, a proportional movement 
will be transmitted to the cut-off valve. To determine the point 
at which the engine is cutting off when running, the plain part of 
the disc,which is connected with the governor and valve-stem, has 
marks and figures upon it, each mark indicating a point in the 
length of the stroke. There is a point which coincides with these 
marks, and can be seen under the pulley attached to the governor. 
To increase or diminish the speed, a counterweight is attached to 
the end of the governor-spindle, under the steam-chest. 

These engines possess many excellent features. The bearings 
are well proportioned and all the parts thoroughly fitted; the 
fly-wheels are turned on the face and sides and accurately bal¬ 
anced ; the connecting-rod and crank-shafts are made of the best 
hammered wrought-iron ; the crank- and wrist-pins are made of 
steel; the connecting-rod boxes of gun-metal, and the main-bear¬ 
ings lined with the best anti-friction metal; while the cylinder is 
cast of car-wheel iron, and jacketed to prevent radiation. 


THE ENGINEER’S II ANDY-BOOK. 


197 



Steam-Engine Governors. 


The subject of regulating the speed of steam-engines, and 

more especially those which, from circumstances and the nature 
of the work to be performed, are liable to constant change, has of 
late years received no little attention from engineers and practical 
inventors, and as a result various kinds of governors have been 
introduced. It would be safe to say that this device has absorbed 
more thought, and re¬ 
ceived more attention 
on the part of mechan¬ 
ics, than any other ad¬ 
junct of the steam-en¬ 
gine. In the ordinary 
governor, the principal 
part of the apparatus 
consists of a pair of 
balls revolving round 
a vertical axis or spin¬ 
dle driven by a train 
of mechanism, gener¬ 
ally mitre-gears, which 
causes their angular ve¬ 
locity of revolution to 
bear a fixed ratio to the 
velocity of the prime 
mover. The rods of 
the pendulums place 
themselves at an an¬ 
gle with the vertical 
axis, so that the common height of the pendulums is that corre¬ 
sponding to the number of turns in a second. The regulator must 
be so adjusted as to be in the proper position for supplying the 
proper amount of power when the pendulum-rods are at the angle 
of inclination corresponding to the proper speed of the machine. 

17 * 


The Waters Governor. 









































































198 


THE ENGINEER’S HANDY-BOOK. 


When the speed deviates above or below that amount, the out¬ 
ward or inward motion of the pendulum-rods acts on the spindle, 
so as to open the valve when the speed is too low, and close it 
when it is too high. 

In the attainment of this object, the principle of centrifugal 
force, as embodied in the old fly-ball governor of Watt, has been 
more resorted to than any other; but, aside from this, the governor 
has been so improved, altered, and reconstructed, since his time, 
as to be almost unrecognizable; but still the old principle is 
there, and also the three prominent defects which so materially 
interfere with its efficiency. The first of these is friction which 
arises from the joints, and is caused by swinging the balls or 
weights by the short end of the arm or lever to which they are 
attached. The second defect is due to the fact that the balls, as 
they assume different positions in keeping with the speed with 
which they revolve, are obliged to rise or fall. This is necessary 
in order that the resistance which the weights offer to centrifugal 
force should constantly increase; if it did not so iucrease, the 
weights, when once started from their position of rest, would in¬ 
stantly go to the extreme limit of motion. The rising of the balls 
shortens theTdistance which they are allowed to move for a given 
variation by bringing the centres of ball and arm on which they 
swing into a straight line, so that a variation which moves the 
balls a given distance upward, if it occurs again, will not move 
them nearly so far in the same direction. Again, the same force 
that would support the balls in any plane would not raise them 
to that plane from a lower one. So between friction, which de¬ 
stroys the delicate power that the balls assume under a slight 
change, and the necessity for a large change to overcome their 
inertia, it is almost impossible to attain a degree of regulation 
which would be equal to all requirements. 

Governors when attached to throttle-valves work under cir¬ 
cumstances that necessitate the use of openings for the passage of 
the steam that are too small in area, so much so that the useful 
effects of the steam are considerably diminished. On this depends 


199 


THE ENGINEER’S HANDY-BOOK. 

the ill repute of throttling engines as compared with those which 
regulate by governor controlled valve motions or variable cut-off*. 
If the valve of a governor has too large openings, it will, owing 
to the unsteady action of the governor, admit too large a quantity 
of steam, and cause a jumping of the engine; then, in trying to 
shutoff this extra amount, it shuts it all off; in fact, the governor 
cannot fix it exactly right, being incapable of delicate changes. 
This difficulty is best met by making the openings in the valve 
of peculiar shape, so that they open and close in a ratio different 
from that of the governor. With a governor that would run per¬ 
fectly up to theory, and be steady and capable of taking a posi¬ 
tion in keeping with the speed, 
and not leaving it without a 
change in speed, a very large 
area might be used, and the 
useful effects of the steam would 
not be impaired, neither would 
there exist a necessity for great 
changes in speed to get the re¬ 
quired opening and closing of 
the valve. The extra amount 
of steam required to drive a 
heavy addition of load on an 
engine is surprisingly small, 
provided that the engine can get 
the steam at the very instant the 
load is applied, and before the 
momentum of the machinery 
becomes much reduced; but 
let the engine once get below 
speed, the circumstances will 
be very different, as, even with¬ 
out any load, the engine would take some time to come to speed. 

The third defect in governors on throttling engines is that the 
spindle or valve-stem has of necessity to pass through steam-tight, 






















200 


THE ENGINEER’S HANDY-BOOK. 

packing- or stuffing-boxes, which have to be screwed up to pre¬ 
vent leakage, without any guide save the judgment of the en¬ 
gineer, which increases the friction and interferes with the free 
action of the governor. There is also the friction on the governor- 
valve necessary to overcome the power required to move the 
valve-stem through all its bearings, stuffing-boxes, guides, etc., 
under the pressure of steam. Were it possible to construct a 
governor for throttling engines which would approach in practice 
what theory would demonstrate, the fly-ball or centrifugal gov¬ 
ernor would be a perfect regulator; but this appears, according to 
mechanical laws, to be impossible. By the use of isochronous 
governors, which would not admit of any variation of speed, but 
would be in equilibrium at any speed, whether the balls were up 
or down, or in any other position, the defects of the common gov¬ 
ernor were supposed to be obviated; but it was found by expe¬ 
rience that power and stability were necessary, and isochronism 
in its strict sense unattainable. 

The economy of a good governor has rarely been appreciated 
by owners of steam-engines and steam-users. t Experience has 
shown the speed best adapted for each and every process in the 
manufacturing and mechanical arts, and the governor that fails 
to meet all the varied requirements of each process is of no value 
in an economical point of view. Every stroke which an engine 
makes below its regular speed increases the cost of production, 
and every stroke above it is a waste of steam, and consequently 
of fuel. If an engine is geared to run at 80 revolutions per 
minute, when a heavy piece of machinery is thrown off, the 
governor admits of an increase of speed of from 10 to 15 revolu¬ 
tions per minute. This incurs a waste of power, and consequently 
a waste of from 12 to 20 per cent, of fuel. On the other hand, 
when a heavy piece of machinery is thrown on, the governor 
allows the engine to lag behind its regular speed by from 10 to 15 
strokes per minute; this increases the cost of production. If a gov¬ 
ernor is unreliable, it is worthless; if reliable, its first cost is merely 
a nominal consideration. There are many processes, such as mill- 


. THE ENGINEER’S HANDY-BOOK. 201 

ing, weaving delicate fabrics, printing from small type, or the very 
accurate turning of fine material, where a good governor is of 
immense value. Unfortunately for the progress of the mechanical 
arts, no governor yet invented has met all the necessary require¬ 
ments, or the varied circumstances under which they are employed. 

Governors are sometimes attached to marine engines for the 
purpose of equalizing the revolutions in heavy sea-ways, and pre¬ 
venting the engines from racing, which is caused by an insufficient 
immersion of the paddle-wheels or propellers, and which may be 
ascribed either to the lightness of the load or the heavy swell 
of the sea. But from whatever cause racing may occur, it is 
always attended with danger, as the undue strain to which the 
machinery is subjected is liable to result in a breakdown. Marine 
governors have not proved a success up to the present time, nor 
has any one yet been invented which may be adapted to all classes 
of marine engines. 

Governors should be kept perfectly clean and free from accu¬ 
mulations induced by the use of inferior oil, as such gummy sub¬ 
stances have a tendency to interfere with the easy movement of 
the different parts. Many first-class regulators have been con¬ 
demned as not being capable of controlling the engine at a uniform 
speed, when all that was required was a good cleaning. 

Governor-spindles working through stuffing-boxes should be 
frequently and carefully packed, as, when the packing becomes 
old and dry, if screwed up to prevent leakage, it interferes with 
the free action of the governor. 

Rules for calculating the size of pulleys for governors.— To find 
the diameter of the governor shaft-pulley. Multiply the number of 
the revolutions of the engine by the diameter of the engine shaft- 
pulley, and divide the product by the number of revolutions of 
the governor. 

To find the diameter of the engine shaft-pulley. — Multiply the 
number of revolutions of the governor by the diameter of the 
governor shaft-pulley, and divide the product by the number of 
revolutions of the engine. 


202 


THE ENGINEER’S HANDY-BOOK. 


How to Balance tlie Reciprocating and Revolving Parts of 

Yertical Engines. 

If the counterweight be so arranged as to describe a circle of 
the same radius as that of the crank-pin, it must be as heavy as 
the piston, connecting-rod, and crank-pin ; but if it has a greater 
circle than that of the crank-pin, it may weigh less than the 
piston and its connections ; the only material condition being, that 
the momentum, or amount of mechanical power resident in the 
counterweight when moving in one direction, shall balance the 
momentum of the piston and its connections when moving in the 
opposite direction. 

When a vertical engine runs slow, the weight of the piston 
and piston-rod, cross-head, connecting-rod, and crank-pin must be 
counterbalanced so that it will stand still in any position; but 
when the speed is very high, it is necessary to counterbalance 
only such parts as revolve round the centre of the shaft, the crank- 
pin, the stub-end, and half the connecting-rod. It is customary 
to give more steam-lead on the valve at the bottom than at the 
top of the cylinder in order to compensate for the weight of the 
piston. 

Heating in Journals and Reciprocating Parts of Steam- 

Engines. 

Heating in the journals and reciprocating parts of steam- 
engines may be attributed to the following causes: bad proportion, 
improper fitting, unsuitable material, want of homogeneity between 
the materials of which the journals and bearings are composed, 
the reciprocating or revolving parts being out of line, the boxes 
being screwed down or keyed up too tight, dirt, sand, or grit get¬ 
ting into the journals, want of proper lubrication, etc. The last 
mentioned cause is much more complicated .than would at first 
sight appear, as there are many conditions to be taken into con¬ 
sideration, among which may be enumerated weight of load, area 
of surface subjected to pressure, velocity of movement, etc. 


the engineer’s handy-book. 


203 


Reversing-Gear for Marine Engines. 

In the early days of the steam-engine, the only reversing- 
gear in use was the V hook, which was very imperfect, uncertain, 
and unreliable in action and 
difficult of adjustment, and, 
in consequence of its action 
being positive, steam could 
not be worked expansively 
on engines on which it was 
employed. A more modern 
arrangement was the loose 
eccentric, which, in conse¬ 
quence of the eccentric-hook 
being thrown out of gear, 
moved half-way round on the 
shaft whenever it became 
necessary to reverse the en¬ 
gine. The most perfect re¬ 
versing and expansion gear 
ever employed in connection 
with the steam-engine is the 
link. 

A A shows the bed-plate; 

B, the pillow-block bearing; 

D, the shaft; EE, the eccen¬ 
tric-rods ; C, the connecting-rod ; F , the link ; G , the cross-head 
wrist; J, the bonnet of steam-chest; IH, the steam-cylinder; K, 
the cylinder-head ; L, the steam-pipe ; M, the front column which 
supports the cylinder; N, the reach-rod; 0, the reverse arm of 
the bell-crank by which the link is moved back and forth; P, the 
lifting arm ; R, the screw by means of which the link is reversed; 
3 3, the guides through which the spindle of the screw, R, moves; 
Q, the hand-wheel by which the lifting arm, P, is moved up or 
down for the purpose of changing the position of the link. 













































































































































































204 


THE ENGINEER’S HANDY-BOOK. 






/ 



The annexed Cuts show the Position of the Slide-Valve at 
Three different Points in its Travel. (See explanation on 

page 206 .) 






































































































THE ENGINEER’S HANDY-BOOK. 


205 


The Slide-Valve. 

The function of the common slide-valve is to admit steam to 
the piston at such times when its force can be usefully expended 
in propelling it, and to release it when its pressure in the 
cylinder is no longer required. Notwithstanding its extreme 
simplicity as a piece of mechanism, no part of the engine is more 
puzzling to the average engineer when the problem to be solved 
is to determine beforehand the results which will be produced 
by a given construction and adjustment, or the proportions and 
adjustment required to produce given results. All who have had 
any experience in constructing and setting slide-valves are aware, 
in a general way, that the events of the stroke cannot be inde¬ 
pendently adjusted; that, for instance, a cut-off earlier than about 
three-fourths of the stroke can only be had at the expense of more 
or less distortion of the other events, and that for some reason, not 
always apparent, it is impossible to completely equalize the events 
of the two strokes, occurring during one revolution. 

But hitherto no simple means have been given by which to de¬ 
termine exactly the degree in which a given change in any event 
affects the rest. There is no lack of literature on the subject, but 
the manner in which it is generally treated is calculated to be¬ 
wilder the average reader more than to assist him; to invest the 
subject with additional difficulties rather than to simplify it. The 
manner in which the slide-valve performs its functions cannot be 
at once perfectly shown without the aid of a working model, but 
a considerable step may be taken in this direction by the con¬ 
struction and study of diagrams similar to the following. It 
should be understood, however, that the measurements given of 
lead, cut-off, compression, etc., are only approximately correct; the 
object being to give the methods by which correct results may be 
obtained rather than the results themselves. 

Fig. I, page 207, represents the position of the piston and valves 
at the beginning of the stroke, when the latter is just commencing 
to open. The motion of both, as will be observed, is to the left. 

18 


206 


THE ENGINEER’S HANDY-BOOK. 


Fig. 2 shows the relative position of the piston and valve 
at about i of the stroke; supposing the travel to be equal to the 
sum of the width of both steam-ports and the steam-lap at both 
ends, so that the ports will be just opened full for the steam, the 
valve will be moving to the left. When the piston reaches the 
left end of its stroke, the valve will have moved to the right till 
it begins to admit steam, at the left hand end, just as Fig. 1 shows 
the admission taking place at the other end, and during the return 
stroke, the conditions represented by Figs. 2 and 3 will follow in 
succession, at nearly corresponding points in the travel of the 
pistons. If the piston was connected to the crank by means of a 
slotted yoke, the events of the two strokes would occur at exactly 
corresponding points in the travel of the piston, but the connecting- 
rod unavoidably introduces a certain amount of distortion, the 
nature and extent of which will be explained hereafter. Fig. 3 
shows the position of the valve at mid-travel, or when of 
the stroke is complete. The compression at the left end towards 
which the piston is moving has just commenced, and the exhaust 
is about to take place from the other end. The events which occur 
in connection with the slide-valve, viz., admission, suppression, re¬ 
lease, and compression, may be explained as follows: — To find 
the cut-off, exhaust, exhaust-closure, port-openings, and angular 
advance which will be produced by a given lap, lead, and valve- 
travel, the lead and laps being equal at the two ends. Suppose 
the data to be as follows : valve-travel 2f in., lap T %, lead in, 
stroke of engine 24 inches. 

Draw the circle A E B G , etc., the diameter of which may, 
when the engine is of considerable size, be equal to the travel of 
the valve, as in the present case. Draw the line A B through 
the centre of the circle, continuing it beyond B to a distance 
nearly equal to three times the distance A B. With the given 
lap in the compasses, draw short arcs of circles at D and E from 
the centre, C. Draw lines a b and c d , parallel to each other, 
touching the arcs D and E, equidistant from the intersections of 
the line A B, with the circle equal to the given lead. Set the 


THE ENGINEER^ HANDY-ROOK. 


207 



compasses to a distance which will be to A B as the connecting- 
rod is to the stroke ol the engine, which in the present case is 
about in.; and with the foot in the continuation of the line A 
B , draw arcs b e and df, which will locate the points of cut-off,/ 
and e on line A B, which represents the stroke of the engine as 
well as the travel of the valve. By constructing and applying a 
scale, such as Fig. 1, in which the travel of the valve is divided 


into as many parts as there are inches in the stroke of the piston, 
it is found that, as the piston moves from the shaft, the cut-off, e, 
takes place at 18| inches from A, and the other, /, at 19§ inches 
from B , making an inequality of H inches. 

If the valve has no exhaust-lap at either end, working “line on 


In 11 111 ii ii i i 1 i i 

3 6 9 12 15 18 21 24 

Fig-. 1. 


















208 


THE ENGINEER^ HANDY-BOOK. 


line,” as it is sometimes called, draw line k l through the centre 
C, and parallel to a b and c d, and from k and l draw arcs 1c h 
and l g , as directed for the arcs df and b e , which will locate the 
points of exhaust and exhaust-closure at h and g , about 1 j and 
1J- inches respectively from the ends of the stroke. A represents 
the end of the stroke nearest the crank ; and it will be observed 
that the events occurring nearest that end are later in the stroke 


L 



than corresponding events at the other end, which will always be 
the case when the laps are equal at the two ends of the valve. 
The port-openings will be D F and E G; FL will be the angular 
advance. 

To equalize the cut-off.— By inspection of Fig. 1, it is evident 
that if line a b be moved towards the centre, C, the arc b e will 
approach B, and cut-off e, which is earliest, will be made later. 













THE ENGINEER’S HANDY-BOOK. 


209 



Fig-. 3. 

that the lead at B required diminishing, the lead at that end may 
he rejected altogether, which will he represented by drawing a line 
from d to B. Then a line from b parallel to it will cut the circle 
at a, indicating that over T % of an inch lead will be required at 
that end (nearest the crank as before explained), against none at 
the other to equalize the cut-off at three-fourths stroke. From 
this it will be seen that the cut-off can only be equalized at the 

expense of the equality of the lead. 

18 * O 


In like manner if line c d be moved farther from the centre, cut¬ 
off* / will be made earlier. These changes represent increased 
lead at A and diminished lead at B. In constructing a diagram, 
however, representing a given equalized cut-off, it will be prefer¬ 
able to begin by locating the points of cut-off at the desired part 
of the stroke, say three-fourths, as at/ e, Fig. 2, from which points 
draw the arcs e b and f d. Then, as inspection of Fig. 1 has shown 














210 


THE ENGINEER^ HANDY-BOOK. 


To equalize the exhaust at a given part of the stroke. Sup¬ 
pose the desired point be 1J inches from the end; set off the 
points at h g, Fig. 2, and draw arcs, h H and g G , as before 
directed. Then supposing the angular advance, F L , and with it 
the lines, a b and B d , to have been fixed, draw HI and G J 
parallel to a b and B d r and from points I and J draw arcs I i 
and J j, which will locate the points of exhaust-closure at j and i. 
The distance, C K, will be the exhaust-laps required at the end 
of the valve next the crank, and the distance of line, IH , from 
centre, C, will be the negative lap (i. e., the amount less than no 
lap) required at the other end. To determine whether the dis¬ 
tance of a line indicating the exhaust-lap (as I H) from the 
centre indicates positive or negative lap, observe the effect of in¬ 
creasing its distance from the centre. If the exhaust located by 
it at one end should be made earlier, and the exhaust-closure 
located by it at the other end made later, the lap indicated by it 
is negative. Thus, to move IH farther from C would make ex¬ 
haust ft earlier and exhaust-closure i later; hence it indicates 
negative lap. The reverse effect would follow by moving G J 
farther from the centre ; hence C K is positive lap. 

Fig. 3. To compromise between unequal lead and cut-off.— 
The lead inequality shown to be necessary, in order to obtain 
equal cut-off, may be in some cases so undesirable as to render 
only a partial equalization of the cut-off preferable. Fig. 3 
shows such a compromise. It shows that by giving -J inch lead 
at A, and none at B, the cut-off will be sufficiently equalized for 
all practical purposes, as the difference is reduced about one-half 
as compared with Fig. 1. It will also be noticed that in Fig. 3 
the exhaust-lap has been increased to T 3 g at C K, and about A 
inch at C m, both positive, which gives equalized exhaust-closure 
at J j, and very nearly equal exhaust at h g. The excess of lead 
at A over B of course diminishes the lap CD, and increases the 
port opening, F D, at that end. 

Fig. 4 shows the data obtained from Fig. 3 applied to the con¬ 
struction of a common slide-valve. The scale of the valve is 


THE ENGINEER^ HANDY-BOOK. 


211 


made one-half size for convenience. The valve is shown at mid¬ 
travel; C k shows the exhaust-lap obtained from Fig. 3 at C k 
and b m; that at C m, steam-lap; a E is obtained from Fig. 3 at 
C E; and c D in like manner from CD. It will be seen that, 
notwithstanding there is less steam-lap at D than at E, the lap k 
D is slightly greater than Em, which is due to the fact that the 
exhaust-lap added at k, to equalize the exhaust and compression, 



Fig-. 4. 


slightly more than compensates for the lesser steam-lap at D. If 
the steam-lap at D had been lessened until h D equalled E m, the 
cut off would have been more nearly equal than is shown on Fig. 
3, but still not entirely so. From this it will appear that valves 
may be constructed (as they mostly are) with the two laps equal 
in width, and in setting them, the exhaust and compression may 
be equalized, letting the cut-off equalization take care of itself, 
which it will do by becoming a trifle more than half equalized, 
as compared with Fig. 1. Such a valve, considered apart from the 
seat on which it works, would appear to have equal laps of both 
kinds, and might be so set, as is the case in the adjustment repre¬ 
sented by Fig. 1; but, when set to equalize the compression and 
exhaust, it must be considered as having unequal laps of both 



















212 


THE ENGINEER^ HANDY-BOOK. 


kinds. A valve constructed from the dimensions furnished by 
Fig. 2, in which, as we have seen, the cut-off, exhaust, and com¬ 
pression were entirely equalized at the expense of lead, equality 
would have the lap k D the shortest. 

In determining the best point for exhaust-closure, it should be 
borne in mind that this event is the one which stands most in the 
way of an early cut-off, and that it is desirable to know how early 
it may be located, without detriment to the performance of the 
engine. The decision of this point will depend mainly on the 
amount of clearance present. If the clearance is great, consider¬ 
able compression is not only admissible, but desirable; as the 
greater the clearance the less the loss of mean effective pressure 
by the counter-pressure resulting from early exhaust-closure. The 
steam shut in by the closure of the exhaust is saved, to be used 
over again during the next stroke; and, when the clearance is 
great, the loss of power by early compression is more than com¬ 
pensated by the saving of steam; the result is a certain amount 
of net gain in economy. As a general rule, the maximum com¬ 
pression pressure should not exceed the pressure present in the 
steam-chest. If it should, the valve is liable to be forced from 
its seat; and not only so, but the limits within which compression 
improves the economy would be exceeded. 

When the clearance is known, and is reduced to a certain per¬ 
centage of the stroke, the compression may be fixed at three to 
five times the clearance, which would, theoretically, raise the com¬ 
pression pressure to from three to five atmospheres; but, in prac¬ 
tice, the theoretical maximum is seldom reached. Thus, suppose 
the clearance of an engine to be equal to its displacement during 
one inch of its stroke, and the valve to close the exhaust four 
inches from the end of the stroke; or, in other words, suppose the 
compression to be four times the clearance, the maximum compres¬ 
sion pressure should, theoretically, reach 55 to 50 lbs.; but it will 
seldom, in practice, exceed 50 lbs., unless the cylinder is jacketed 
with live-steam, and the valve and piston are very tight. 

The proper point to release the steam will depend upon the 


THE ENGINEER’S HANDY-BOOK. 


213 


travel of the valve, the capacity of the cylinder-ports, and the 
exhaust-passage in the valve. If these are ample, the release may 
occur later than when they are not. The point to he aimed at in 
locating it, is to release in time to avoid any considerable back 
pressure at the beginning of the return stroke. No responsible 
engine-builder of the present day will fix on a valve construction 
and adjustment permanently, until he has first tested its results 
uith the indicator, and satisfied himself that they are the best 
possible with the slide-valve. 



The above cut represents the Myers slide-valve. C C shows 
the main valve, which is whole stroke; DD shows the cut-off, 
what is termed the riding cut-off, because it rides on the back of 
the main valve, and, as will be observed, the amount of expansion 
is regulated by right and left hand screws passing through the 
cut-off valves, and shown above, D D. By turning the hand- 
wheel, L, to the right, the cut-off will be decreased, while by turn¬ 
ing to the left it will be increased. H H shows the steam-ports ; 
0, the exhaust cavity, and F, the exhaust opening in the valve- 
face; J J, the valve-stems passing through guides on the back end 
of the stuffing-box ; K K shows the bonnet of the steam-chest; 
and M, the spindle which carries the right and left screws. I is 
the main valve-stem ; N, a bracket for the purpose of holding the 
quadrant, 0 , in position, and preventing the cut-off from varying 
when it is once set. This description of valve is used on nearly 
all large ocean steamers. 



























































214 


THE ENGINEER’S HANDY-BOOK. 


The Wheelock Automatic Cut-Off Engine. 

The cut on page 215 shows the cylinder, valve-gear, gov¬ 
ernor, and part of the housing of the “ Wheelock Automatic Cut- 
Off Engine,” and that on page 216 a section of the same. In 
general appearance, the Wheelock engine bears a close resem¬ 
blance to the Corliss type, except that the absence of the cut-off 
valves at the top of the cylinder removes the necessity for the 
square corners, and that the guides, though like those of the Cor¬ 
liss, are parallel with the plane of vibration of the connecting- 
rod, and, in place of being V-shaped, are curves bored out on a 
line with the axis of the cylinder. This insures perfect accuracy, 
and prevents the possibility of the piston and cross-head getting 
out of line. 

The valves receive their motion from an ordinary eccentric, and 
perform the double function of admitting and cutting off steam. 
Their seats are as close to the bore of the cylinder as is consistent 
with a proper allowance of material, thus reducing the clearance 
to a minimum. The valve-motion is very ingenious, effective, and 
simple. The cut-off is effected by tripping the valves with an ar¬ 
rangement which dispenses with the necessity of dash-pots, weights, 
or levers, as by means of lugs on the lifters coming in contact 
with the spring catches, which engage rock-arms on the valves, 
the same effect is produced. The governor is of a design pecu¬ 
liarly adapted to these engines, and, in consequence of its sensi¬ 
tiveness, holds the valve-gear under complete control, and insures 
a steady motion of the engine under the most varying circum¬ 
stances of load and pressure. 

The Wheelock engines are in very general use in the East¬ 
ern States, and seem to give satisfaction. One of them which 
was running in the Agricultural Department of the Centennial 
Exhibition, held at Philadelphia in 1876, attracted a good deal 
of attention, on account of its smooth and noiseless working. The 
most objectionable feature of these engines is the liability of the 
valves to become leaky. 


Back View of Wheelock’s Automatic Cut-Off Engine, with the Valve-Gear Unhooked. 


THE ENGINEER’S HANDY-BOOK 


215 






























































































































































































































































216 the engineer’s handy-book. 



Section of the Cylinder, Piston, Steam- and Exhaust-Valves of Wheelock’s 

Automatic Cut-Off Engine. 






















































































































































































































































































































THE ENGINEER’S HANDY-BOOK. 


217 


Lap on the valve. —The term lap on the valve denotes the 
amount the edges of the valve extend over the ports when the 
valve is in the centre of its travel. If a valve has g lap, it is 
understood to extend g beyond the ports when placed centrally 
over them. The object of lap is to secure the benefit to be derived 
from working steam expansively. Lap on the steam side is termed 
outside lap, while lap on the exhaust side is termed inside lap. 

Poppet- or conical-valves cannot have any lap; but the same 
effect is produced, as in the case of the slide-valve, by arranging 
the cams and lifting-toes so that the valve may close at the proper 
time to give the necessary degree of expansion. The lift of poppet- 
valves, to give an opening equal to the area of the port, is ^ the 
radius or | the diameter. 

Lead on the valve. —The object of lead is to enable the steam 
to act as a cushion against the piston before it arrives at the end 
of the stroke, to cause it to reverse its motion easily, and also 
to supply steam of full pressure to the piston the instant it has 
passed dead-centre. It varies in different engines from gb to T 3 g, 
without regard to size or kind. It often, however, exceeds 
but perhaps very seldom ; while some valves have no lead at all, 
others less than none, or what is termed “ negative lead.” The 
higher the speed and the more irregular the work the more lead 
will be required for any engine. 

Loss of lead is a term employed to express the inequalities of 
the lead at one end of the cylinder induced by the expansion of 
valve-rod. It may occur, however, at both ends, through lost 
motion in the joints or displacement of the eccentric. 

Lead on the steam end is a term applied to the amount of 
opening the valve has at the end of the cylinder into which the 
steam is entering. Lead on the exhaust end means the amount 
of opening the valve has on the end from which steam is escaping. 
The name applies alternately to each end of the cylinder. 

Line and Line. —A term applied to slide-valves when they 
have no exhaust lead, as shown in Fig. 3, on page 204. 

19 


218 


/ 


THE ENGINEER’S HANDY-BOOK. 

Valve-seat. —The flat surface which contains the ports, and on 
which the valve moves. 

The valve-face is the working surface of the valve which moves 
on the valve-seat. » 

Valve-circle. — The term valve-circle, though sometimes used, 
is inappropriate, as a valve does not describe a circle. It means 
a circle which would have a circumference equal to the distance 
travelled by the valve in two strokes or one revolution. Such a 
circle would be smaller than that described by the centre of the 
eccentric, unless, as is sometimes the case, the rocker-arms were 
so arranged as to give a greater travel to the valve than to the 
eccentric. 

Valve-stroke. — The travel or stroke of a slide-valve is the dis¬ 
tance it moves on its face to give the proper opening of the port. 


How to Determine the Amount of Lap and Lead on a Valve 
without Opening the Steam-Chest, and whether it is Equal 
at hotli Ends or not. 

Open the cylinder drain-cocks and disconnect them from the 
drip-pipes, so that the steam may be seen and heard to issue from 
them. A better plan is, to open the holes made for the indicator, 
if there are any; at all events, open as large holes as possible; then 
let in a very little steam, turn the engine around by hand, and 
note, by the commencement and cessation of the flow of steam, 
just where the steam is admitted and cut-off. The point of cut¬ 
off can be most accurately ascertained by turning the engine 
backwards; the steam will in this case commence blowing at the 
same point in the stroke at which it would cease blowing when 
turning it forward; and, owing to the elasticity of steam, the 
commencement of the issue is always more clearly defined than 
the cessation, particularly when the issuing orifice is small. For 
the same reason, the point of admission can be most accurately 
located by turning the engine forward. 


THE ENGINEER^ HANDY-BOOK. 


219 


To determine the lead, having found the point of admission, 
make a mark on the valve-stem at a known distance from some 
fixed point, and another after the pin has reached the centre; this 
will give the lead. If the admission forward takes place when the 
crank-pin is exactly on the dead-centre, there is no lead. Having 
obtained the lead and cut-off for both ends, the travel and length 
of the connection being known, a diagram may be constructed 
similar to Figs. 1, 2, and 3, which will give the lap and port-open¬ 
ing. 

The point of exhaust and compression cannot be determined so 
readily. With a small engine, in which the piston and valve are 
steam-tight, the points may be ascertained by blowing into the 
cylinder through pipes attached to the cylinder-cocks or the holes 
for indicator, if any. The exhaust would be indicated by the 
point where the air would begin to pass through into the exhaust, 
and the closure, by noting the point where it ceased to pass 
through. 

But in engines of any size, especially leaky ones, the plan of 
blowing in with the mouth would be inapplicable. With non¬ 
condensing engines, however, much may be learned by listening 
to the exhaust; if the puffs occur at equal intervals, and are of 
equal force, good equalization may be inferred; and, if they are 
short, quick, and free, and are followed by a free and nearly noise¬ 
less escape of the residuary steam, the exhaust is early and ample 
enough. On the other hand, too late an exhaust will produce 
more prolonged and labored puffs. It is needless, however, to 
remind the reader that nothing can take the place of the indicator 
for determining all the conditions and adjustments of the valve, 
particularly its exhaust and compression, as, even when the nicest 
measurements and calculations are resorted to, doubts may still 
exist as to the truthful movements of the valve, which nothing 
but an application of the indicator can satisfactorily remove. 


220 the engineer’s handy-book. 

TABLE 

SHOWING THE AMOUNT OF “ LAP ” REQUIRED FOR SLIDE-VALVES WHEN 
THE STEAM IS TO BE WORKED EXPANSIVELY. 


When the travel of the valve is known, and the point of cut¬ 
off decided, the following table will show the amount of lap re¬ 
quired.* 


Travel 
of the 
Valve 
in 

Inches. 

The Travel of the Piston when the Steam 

is cut off. 

i 

4 

1 

3 

5 

1.2 

1 

2 

7 

T2 

f 

3 

4 

10 

1 2 

The required “ Lap.” 

2 

7 

8 

3 

4 

11 

TS 

5 

8 

9 

1 6 

1 

2 

7 

1 G 

1 

3 

8 

2} 

lye 

1 

7 

8 

1 3 

1 G 

1 1 

T 6 

9 

1 6 

1 

2 

- J 

1 6 

3 

H 

1_3_ 

i 16 

H 

1 

1 5 

1 6 

3 

4 

5 

8 

9 

1 6 

31 

i-i 

x 1 6 


1* 

IjG 

1 

7 

8 

3 

4 

4 

if 

19 

1 1 6 

l- 7 - 
X 1 6 


H 

1ft 

1 

1 3 

1 6 

44 

2 

I IS 

I I 6 

I- 9 - 
x 1 g 


H 

U 

14 

7 

8 

5 

9 1 

Z 8 

2 

113 
x 1 6 

1ft 

U 

i| 

11 

1 

54 

9 5 

Z 1 <5 

2- 3 - 

6 

2 

1M 
x 1 G 

x 8 

1 1 

A 2 

11 

14 

6 

24 

9 7 

2- 3 

2 

113. 

1 1 6 

1 4 ?- 

X 8 

14 

1 3 

X 7 S 

64 

2f 

9 9 

Z T 8 

9 7 

Z 1 6 

9 3 

Z 3 4 

2 

1 

X 1 6 

1 5 

11 

7 

3 

91 1 
Z T 6 

9 9 
z Tg 

2 1 

9 3 

2 

1 J 

14 

74 

Q 3 

°1 S 

3 

9 ' 1 
Z T6 

2 i 

2 1 

9 3 

Z 32 

1 7 

14 

8 

3—L 
°1 6 

3 fV 

3 

9 5 

L 8 

2 -1 

9 3 

2 

if 

«1 

Q 5 

6 8 

3 T6 

3 T6 

9 1 3 

Z 1 6 

91 1 

Z 1 6 

24 

9 1 

w 8 

l| 

9 

315 

31 

3ft 

3 

91 3 

Z 1 6 

911 

Z 1 6 

9 1 

z 4 

1 l 

8 

n 

4 

3 1 3 
°T6 

31 

3- 3 - 
0 1 6 

3 

91 3 

9 3 

Z 8 

2 

10 


4 

Q 1 3 
^16 

Q 5 
^ I <3 

3ft 

3 

2 J 

2_J 

Z 1 6 

101 

4ft 

4 1 

4 

4 

34 

3 ft 

84 

21 

2ft 

11 

4 - 9 - 

^16 

4 7 

I 6 

4 -i 

3 g 

3 i 

3 A 

21 

2{ 

B 4 

41 3 
^1 6 

4 9 

1 6 

4- 7 - 

31 

3 f 

8 * 

9 7 

Z 8 

2 * 

12 

5 

41 3 
^ I 6 

4_9 

M 6 


4 

3 t 

3 

21 


It is not advisable to cut off earlier with a single slide-valve 


* If a valve has f lap, it will overlap each steam-port f of an inch when 
placed centrally over them. 

























THE ENGINEER’S HANDY-BOOK. 


221 


than at 4 or f stroke, as otherwise the lap would be excessive 
and the freedom of the exhaust impaired. In locomotives and 
marine engines the case is different, as the cut-off may be effected 
at almost any point through the agency of the link. 

Rule for finding the point of cut-off required to produce a given 
terminal from a given initial pressure. 

Divide the total terminal by the total initial pressure. The 
quotient will be the point of cut-off in decimal parts of the stroke. 

Example. —Initial pressure, 20 lbs. per sq. in. Terminal, 13 lbs., 
measured from a vacuum. Then 13 lbs. -s- 20 = *65 of the stroke; 
or divide the volume of the initial by that of the terminal, the 
quotient will be the point of cut-off in decimal parts of the stroke. 

Example.— Vol* of 20 = 1229. Vol. of 13 = 1842. Then 
1229 -4- 1842 = '667 of the stroke. 

Rule for finding the point of cut-off when the initial and mean 
pressure are known. 

Add the pressure of the atmosphere to the initial and mean 
pressures, and divide the mean pressure by the initial. Then find 
in the table of multipliers, page 69, the number nearest the quo¬ 
tient. Find the number opposite to it in the expansion column, 
and divide 100 by it; the quotient will be the point of cut-off in 
decimal parts of the stroke. 

Example. —Stroke of piston, 10 ft. Initial pressure, 10 lbs. per 
sq. in. Mean pressure, 8 lbs. Mean effective pressure, atmos¬ 
phere added, 22‘50. Initial pressure, atmosphere added, 24’5. 
Quotient of first divided by last, *918. Expansion number in table 
opposite,'919, which is nearest number to above quotient, 1’6; 100 -s- 
1*6 = ‘625 or f of the stroke. Either of the foregoing rules will 
make the cut-off take place a trifle earlier than it would in practice. 

Friction of Slide-Valves. 

IVIany estimates have been made concerning the power absorbed 
in overcoming the friction of slide-valves, and probably on no sub¬ 
ject has there been a greater diversity of opinion. It has been 

* See Table of Volumes, pages 7 t> to 87 . 

19 * 




222 


THE ENGINEER’S HANDY-BOOK. 


assumed, on the one hand, that as much as one-fourth of the power 
of an engine is wasted, while others claim that the loss of power 
is merely nominal. An idea has been very generally entertained 
by engineers that the number of square inches in a slide-valve, 
and the pressure of steam in pounds per square inch, represented 
the total pressure on its back; or, in other words, that the press¬ 
ure was equal to the pressure of steam per square inch on the 
back of a valve, minus the area of the steam-ports. 

Such conclusions are erroneous, however, as the number of 
square inches in a slide-valve, and the pounds pressure per square 
inch, represent only the weight on its back, if we consider the 
valve as a solid block of iron, with a smooth surface resting on a 
smooth, solid bearing, perfectly steam-tight, in which case the 
steam would press on every square inch of surface with the same 
force as a dead weight. There is good reason to believe that 
such conditions are never found in a slide-valve, except in one 
position, viz., when the valve overlaps both ports and the engine 
is at rest. As soon, however, as the valve moves, the steam enters 
the open port, and the pressure is partially taken off that end of it. 

Rule for finding the pressure on slide-valves. 

Multiply the unbalanced area of the valve in inches by the 
pressure of steam in pounds per square inch ; add the weight of 
the valve in pounds, and multiply the sum by 0T5. 

Another rule. — Multiply the combined area of the bearing sur¬ 
face and ports in inches by the steam pressure in pounds per 
square inch on the back of the valve; multiply this product by 
the coefficient of friction between the two surfaces. The product 
will be the force required to move the valve when unbalanced. 

The better the slide-valve is fitted, the more power it takes to 
work it; and a valve that is perfectly steam-tight on its seat, 
takes immensely more power to move it than if poorly fitted; 
because, if a valve is leaky, there is always a film of steam be¬ 
tween the valve-face and the seat; but, when the valve is perfectly 
steam-tight, there is nothing to lessen the friction except the lu¬ 
brication. 




223 


THE ENGINEER’S HANDY-BOOK. 



The above cut represents poppet,* or double-beat, valves, such 
as are used in connection with the Stevens’ Cut-Off, or what is 
termed the Stevens’ Front. It will be observed that the valves 
on the left side are open for the admission of steam, while those 
on the right are closed. The lift of such valves, if single, would 
be about | of their diameter ; but when they are double, as in 
the present case, -£■ lift would give an area equal to the opening of 
the steam-port. One of the greatest difficulties experienced in the 
working of such valves is, that, however carefully they may be 
fitted, their stems will expand and induce leakage in the valves 
when exposed to a high temperature. For this latter difficulty 
there appears to be no remedy. 

Nevertheless such valves have their advantages, among which 
are, that they can be turned up, or ground on to their seats at a 
moderate cost, since the process of their manufacture is all lathe 
work; that in their working, there is no power absorbed by fric¬ 
tion, as in the case of the slide-valve, and that they can be placed 

* Puppet is the correct word, though poppet is most generally adopted by 
engineers. 



























































































224 


THE ENGINEER^ HANDY-BOOK. 


so near the cylinder as to reduce the clearance to a minimum. 
Such valves, however, would not answer for high-speed engines, 
as at high-piston velocity, and considerable back pressure, they 
would not seat. 

How to Set the Valves of Steam-Engines. 

No definite instructions that would apply to all cases can be 
given for setting the valves of steam-engines. As the circum¬ 
stances under which the engines and valves are employed must, 
to a certain extent, influence and control this operation, fast-run¬ 
ning engines require more lead than those that run slowly. En¬ 
gines doing heavy and irregular work also require more lead than 
those working with a uniform load. Some engines require no lead 
at all, while others require a great deal. 

The valves of a steam-engine may be adjusted with great ac¬ 
curacy by an intelligent and practical engineer, providing that 
all the valve-gear is of correct proportions; but there are diffi¬ 
culties to be contended with which frustrate the efforts of the most 
practical mechanics, and must ever do so, unless we discover a 
new material for valves and valve-gear. Valves may be set with 
the nicest mechanical accuracy, opening and closing the ports with 
precision when the valves and valve-gear are cold; but when ex¬ 
posed to high temperatures they may be far from accurate in 
their travel. All metals expand with heat and contract with cold, 
and a valve that will give uniform lead at each end of the stroke 
when cold, will not, in all probability, do so when exposed to the 
action of the steam, as the valve and valve-rod will expand, pro¬ 
duce a loss of lead, increase the amount of lap, and alter the con¬ 
ditions under which the engine was intended to work. 

This change is not confined to slide-valve engines, as the stems 
of poppet-valves are lengthened by expansion, decreasing the lift 
and also the lead, and inducing a very different condition of things 
from what would exist if the valves could be used at the tempera¬ 
ture at which they were adjusted. Thousands of indicator dia- 
grams show conclusively that the behavior of valves, when exposed 


225 


THE ENGINEER’S IIANDY-BOOK. 

to high temperature, is very different from what they are when 
cold. One of the best aids to correct valve-setting is a good indi¬ 
cator, as nothing shows the action of the steam in the cylinder so 
correctly as this instrument. It tells exactly when the steam goes 
in and out of a cylinder, because it maps down the motions of the 
steam as determined by the motions of the valve and piston, re¬ 
cording faithfully the times and pressures as they actually are. 

To set a slide-valve, place the crank on the dead-centre and 
the valve centrally on its seat over the ports; then adjust the 
valve-gear to the right length, and move the eccentric round in 
the direction in which the engine is intended to run, until the 
proper lead is attained, as shown in Fig. 1, page 204; then turn the 
engine on the opposite centre, and, if the lead is exactly the same, 
the valve ought to travel equally on its seat, and the exhaust 
appear, as in Fig. 2, page 204. Any difference in the lead at 
either end must be equalized by lengthening or shortening the 
valve-gear, as the case may be. 

An intelligent engineer can generally tell by observation whether 
engines exhaust regularly or not; as, if the steam is discharged 
with long or short puffs, alternately, or shows what is technically 
termed a long and short leg, it is evident that the valve has an 
earlier and a freer exhaust at one end than at the other; never¬ 
theless, one exhaust may be heavier than the other, and yet the 
intervals between them may be equal. In such cases the exhaust 
is equal as to time, but not as to amount. The difference in 
amount may be caused by unequal degrees of expansion, and this 
in turn may be caused by unequal cut-off, or unequal clearance, 
or both. Such inequality cannot be cured by mere adjustment, 
since the lap requires to be changed; but in most cases an im¬ 
provement may be effected by a compromise between equalized 
cut-off and exhaust, so that the effects of the inequality of both 
would not be noticeable. 

In the case of fast-running engines, or where the exhaust has 
to pass through long pipes, this inequality is not easily determined 
from the appearance of the exhaust; but it may be done more 

P 

i 


226 


THE ENGINEER’S HANDY-BOOK. 


accurately by holding the ear close to the exhaust-pipe. This 
latter method may also be resorted to in the case of low-pressure 
engines exhausting into a condenser. 

Yalves and Valve-Gear. 

The term valve-gear embraces all intermediate connections be¬ 
tween the eccentric on the driving-shaft and the valves, and is 
applicable to all mechanical arrangements employed for working 
the valves of steam-engines. 

The valves moS generally employed for the admission of steam 
to the cylinders of steam-engines, are the slide, poppet, Corliss or 
semirotary, and rotary ; plug- or piston-valves are also used, hut 
most generally for steam-pumps. All valves, whether used for 
the admission or escape of steam to or from the cylinders of steam- 
engines, receive their motion from cams, eccentrics, or cranks; the 
movements of the former being {indefinite as to character, and of 
the two latter, definite. Whatever the device employed to give 
motion to the valves may be termed, whether cams, eccentrics, 
cranks, gearing, rockers, wrist-plates, toes, lifters, trips, links, rods, 
levers, etc., they may be placed under the head of valve-gear. 

There are engines without valves, such as the Wal’d well, which 
was on exhibition at the Centennial Exposition at Philadelphia, 
and some kinds of oscillating engines, in which faces on the cyl¬ 
inder fit against faces on stationary steam-chests, through which 
the steam enters and escapes from the cylinder. Such arrange¬ 
ments may be called stationary valves, hut they possess inherent 
defects, which render them useless for the most important purposes 
for which the steam-engine is employed. 

A “ releasing ” valve-gear is an arrangement in which the valve 
is liberated from the control of its moving agent, and allowed to 
close in obedience to the action of a spring, weight, or other force 
independent of that which opened it. The agent which deter¬ 
mines the time of release may be the governor, or it may be, and 
often is, some device adjustable by hand. 


THE ENGINEER^ HANDY-BOOK. 


227 


An automatic cut-off valve-gear is one in which the movement 
of the cut-off valve is so controlled by the governor, as to cut off 
the steam as early or as late in the stroke as may be required, to 
maintain the desired uniformity of speed, under variations of load 
and pressure. 

A positive cut-off is an arrangement of valve-gear by which 
the expansion of the steam is effected by what is known as lap on 
the valve, the steam being cut off at the same point in each stroke, 
independent of load or pressure. 

An “adjustable” cut-off is an arrangement of valve-gear, in 
which the point of cut-off can be adjusted by the hand of the en¬ 
gineer, outside of the steam-chest, by means of a screw, hand-wheel, 
or other mechanical arrangement, to meet the requirements of 
work and pressure. The link, in its application to the steam-en¬ 
gine, belongs to this class of cut-offs, as it effects the adjustment 
of the cut-off by means of coincident variations in the travel and 
angular advance using a single valve. 

Riding cut-off. — A term applied to cut-off valves which ride 
on the back of the main steam-valve. 

An independent cut-off is one in which the expansion is effected 
by an independent or auxiliary valve riding on the back of the 
main valve, and receiving its motion from an independent eccen¬ 
tric. 

An “ expansion ” valve-gear is one that cuts off the supply of 
steam at any required point of the stroke. It embraces all the 
foregoing arrangements. 

A “whole ” stroke valve-gear is one that admits steam through 
the whole length of the stroke. 

A “ reversing ” valve-gear is an arrangement employed for re¬ 
versing the motion of engines. It is effected in different ways : in 
some cases with a single eccentric, while in others with two ec¬ 
centrics, as in the case of the link; and in others, still, by means 
of a loose eccentric which revolves on the shaft, but is prevented 
from making a complete revolution by two stops so placed that 
one arrests it in the proper position for the forward, and the other 


228 


THE ENGINEER’S HANDY-BOOK. 

for the backward motion. This arrangement is peculiarly adapted 
to tug-boats and ferries, owing to the ease and quickness with which 
the engine can be reversed. 

Double-beat valves are poppet-valves so arranged, that the 
pressure of steam is nearly equal on both sides, thus rendering the 
motion of the valve much easier than in the case of an ordinary 
single-beat valve. (See cut, page 223.) 

Throttle-valves are valves located in the steam-pipe, through 
which steam is admitted to the steam-chest. At present their use 
is confined to locomotives and old-fashioned stationary engines. 

Relief-valves are used on the cylinders of large engines, par¬ 
ticularly marine, to prevent fracture of the cylinder-head and 
cylinder, in consequence of an accumulation of water in the latter. 
When a greater pressure is exerted in the cylinder than would 
result from the ordinary pressure of the steam, the relief-valve 
will open and admit of the discharge of the water, thus averting 
an accident. They are used on fire-engines for the purpose of 
preventing the hose from bursting when the escape of the water 
is obstructed. 

Balance-valves. —Arrangements by which the weight on the 
back of slide-valves, induced by the pressure of the steam, is re¬ 
lieved by the action of the steam in the steam-chest. 

Rotary-valves. —A term applied to any valve that describes a 
revolution in working. 

Semirotary-valves. —A term applied to all valves similar to 
the Corliss that have a vibratory or rocking motion. 

Starting-valve gear. —A mechanical arrangement employed in 
connection with a small engine, called the starting-engine, for 
moving the valves of large engines when stopping or starting. 

Gridiron-valves. —A modification of the slide-valve, containing 
a number of openings for the steam, by which means its travel 
and friction are materially diminished. 

Dash-pot. —An arrangement employed for closing the valves 
of engines of the Corliss type, and in many instances for arresting 
the closing movement when it is sudden and violent. The dash- 


THE ENGINEER’S HANDY-BOOIv. 


229 


pots contain usually either water or oil, though in many instances 
they are cushioned with air. 

Spring-levers. — Arrangements employed for closing semiro¬ 
tary- and poppet-valves. They are a substitute for the dash-pot, 
which has many advantages over them, on account of the dis¬ 
agreeable noise induced by their workings. 

Lifters. —A term applied to the toes on the lifting-rods, which 
open and close the valves of steam-engines, particularly those 
constructed with what is called a Stevens’ front. 

Wrist-plate. —An arrangement employed in engines of the Cor¬ 
liss type for transmitting the motion of the eccentric to the valves, 
and in many instances for modifying their throw or movement. 

Trips. —A term applied to the pawls which liberate the valves 
of engines having what is termed a releasing-valve gear. 

Crab-claw. —A term applied to the pawls, which liberate the 
valve-gear of engines of the Corliss type from the influence of 
the eccentric, when the point of cut-off is reached. 

Yalves and Cocks Connected with Engines and Boilers. 

The valves and cocks on a ship’s side, in the engine, boiler-room, 
and hold of a steamship, are the injection-, main-, bilge-, discharge-, 
and water-service valves, and the blow-off-, scum-, and ash-cocks. 

The valves on a marine engine that can be worked by hand 
are the stop-, safety-, slide-, throttle-, starting-, feed-, and suction- 
valves. 

The valves that are worked by the motion of the engine are 
the slide, cut-off, or expansion, feed, and bilge-pump, check, and 
discharge valves. 

The valves and pipes, through which the steam passes from the 
boiler to the condenser, are the steam stop-valve on the boiler- 
dome, the steam-pipe, the throttle-valve, the slide- or poppet-valve 
in the steam-chest, and the eduction-pipe between the cylinder and 
the condenser. 

The cocks and valves through which the injection and boiler 
20 


230 


THE ENGINEER’S HANDY-BOOK. 

feed-water passes in jet-condensing engines are the sea-injection 
cock, passing through the ship’s side to the rose-plate in the con¬ 
denser, from which it is drawn off by the air-pump, through the 
foot-valve, and delivered to the hot well, from whence the quantity 
necessary is drawn by the feed-pump, and forced through the 
check-valves iuto the boiler. 



Fig. 2. 


The above cuts represent a simple method of ascertaining 
whether a slide-valve is well proportioned or not, and whether 
the exhaust opens at the right time, too soon, or too late. Dis¬ 
connect the valve from the rod or yoke, and take two parallel 
pieces, A A, about one-half inch thick and one inch wide; though 
the exact width or thickness is immaterial. Let one be the exact 
length of the valve in the direction of its travel, on which the 
width of the exhaust opening, C , in the valve-face may be marked 
by cutting notches with a penknife; then place the other parallel 
piece on the valve-seat, and mark the width of the steam-ports, 
J5, and the exhaust, D. Then place the one representing the 
valve, A, in the centre of its travel, as shown in Fig. 1, and ob¬ 
serve the inside and outside lap; next place it at the commence¬ 
ment of its stroke, as shown at F, Fig. 2, and observe the amount 
of exhaust opening. 










THE ENGINEER’S HANDY-BOOK. 


231 


If it should appear that the valve is well proportioned for 
the admission of the steam, and that the exhaust opens too late, 
the difficulty may be remedied by chipping out the exhaust¬ 
opening in the valve-face; or, should it be found that the exhaust 
opens too early, it may be obviated by inserting some pieces of 
brass or copper, and securing them to the valve with some small- 
tap-bolts, the heads df which may be riveted down; after which 
the pieces may be filed and scraped down to correspond to the 
face of the valve. 

Pipes. 

The principal pipes connected with marine engines and boilers 
are the main steam-pipe, donkey-pipe, cylinder jacket-pipe, whistle- 
pipe, the steam winch-pipe, ballast engine-pipe, feed-pipes, donkey 
feed-pipes, donkey suction-pipes, and a hot-well connection-pipe, 
circulating water-pipes, feed suction-pipes, air-pump discharge, 
bilge-discharge, bilge suction, bilge-injection, cylinder drain-pipes, 
slide-jacket drain-pipes, and steam-jacket drain-pipes, blow-off- and 
scum-pipes, waste-steam pipe, cooling-pipe, water-service pipes. 

The pipes, cocks, and valves used in connection with the loco¬ 
motive are the arch-pipes, blast-pipes, connecting-pipes, oil-pipes, 
steam-gauge pipe, blower-pipe, feed-pipes, heater-pipes, lifting-pipe, 
sand-pipes, steam-pipe, throttle-pipe, blow-off cocks, check-valve, 
cylinder-cocks, feed-water cocks, frost-cocks, gauge-cocks, heater- 
cocks, mud-cock, pet-cock, safety-valve, slide-valve, stop-cock, stop- 
valves, and throttle-valve. 

The pipes, cocks, and valves used in connection with station¬ 
ary engines are the steam-pipe, exhaust-pipe, feed-water pipe, 
blow-off pipe, drip-pipes from cylinder, drip-pipe from heater, 
steam-gauge pipe, slide, poppet, or rotary steam-valves, globe- 
valves on steam- and water-pipes, check-valves, stop-cocks on blow- 
off pipe, bib-cocks, drips, etc. 

Check-valves are placed on the connections between steam- 
boilers and the pump or injector, by which they are fed to resist 
the pressure from the boiler. 


232 


THE ENGINEER’S HANDY-BOOK. 


The Wells Two-Piston Balance-Engine. 

The cut on opposite page represents the Wells Tvvo-Piston 

Balance-Engine, which, the inventor claims, possesses features in 
point of efficiency and economy which place it on a par with some 
of the most improved engines in the country, as it may be run at 
a much higher velocity, and, in consequence of its greater capac¬ 
ity, is more efficient than any single-piston engine in use at the 
present day. The weight and momentum of the reciprocating 
parts being equal in opposite directions, the action is perfect 
without lead, which results in a great saving of steam ; and as the 
force is applied on opposite sides of the shaft, and both cranks 
travel in the same direction, the thrust- due to a single crank, is 
avoided. Moreover, because all the force of the steam on the 
cranks is exerted in torsion, there is no strain on the housing or 
foundation; hence it requires only a slight foundation. They have 
been frequently run at a piston speed of 1000 revolutions per min¬ 
ute, without any perceptible jar to the engine or vibration in the 
building. 

It is further claimed that the advantages of high piston speed, 
and the benefits to be derived from expansion, are more fully 
realized in this engine; and that the condensation is less than it 
possibly can be in any single-piston engine. Besides, the weight 
of these engines is only about one-fourth that of ordinary engines 
of the same power; and, in consequence of the absence of all 
vibration while they are working, they can be placed in any room 
in a building without inconvenience or annoyance, and are pecu¬ 
liarly adapted to yachts and other pleasure boats. The cut on 
page 234 shows a section of the same engine: A A and B B des¬ 
ignate the steam- and exhaust-ports ; C C, the piston-heads ; D, the 
middle piston-rod, which works through the middle piston-head; 
E E, the outside piston-rods; E, the middle connecting-rod; G G , 
the outside connecting-rods; H H, the middle crank-arms; II 
the outside crank-arms; J, the shaft; K shows the line on which 
the opposing strains are exerted. 


THE engineer's handy-book 


233 



The Wells Two-Piston Balance-Engine. 


20 * 






































































234 


BOOK. 


THE ENGINEER’S HANDY- 













































































































THE ENGINEER’S HANDY-BOOK. 


235 


Steam is admitted simultaneously to both ends of the cylinder, 
and exhausted in the ordinary way by means of a slide-valve. 

But as the piston is one of the most important parts of a steam- 
engine, and is oftener a source of annoyance and waste than any 
other adjunct of the machine, it is extremely doubtful if the 
economy of any engine can be increased by-the use of two pistons. 
Such engines, instead of being economical, are more frequently a 
source of expense and annoyance. 

Instructions for the Care of Steam-Engines. 

Never allow an engine to become dirty, as thorough cleaning 
requires no great amount of labor. An engine which has always 
been kept clean,, pro tec ted from rust and not abused in any way, 
is worth, when second-hand, very much more than another which 
has had little attention, been allowed to rust, and to take care of 
itself generally. 

A handsomely kept engine, with all its parts clean and in good 
order, furnishes stronger evidence of an engineer’s capabilities 
than a volume of written recommendations. 

Never depend entirely on patent oil-cups, as they either feed 
too fast or not at all. There is generally too much oil wasted on 
engines. What is needed is a small quantity at the right time, 
and in the right place, and all that is not essential is wasted. 

Do not allow the packing to become hard and dry in the stuffing- 
boxes, as under such circumstances it has a tendency to cut and 
flute the rods. 

Never strike any part of an engine with the face of the hammer 
or head of a monkey-wrench, as, in consequence of their being 
headed with steel, they have a tendency to bruise the parts and 
disfigure the engine. 

Never set steam-packing, cotton-waste, tops of oil-cups, or 

anything that is to be used round the cylinder, valves, piston-rod, 
or bearings of steam-engines, on the floor, as they will invariably 
pick up sand or grit, which injure the rubbing and revolving sur¬ 
faces with which they come in contact. 


236 


THE ENGINEER’S HANDY-BOOK. 


When practicable, piston and valve-rod packing should be ap¬ 
plied when the stuffing-boxes and rods are cold. The best pack¬ 
ing is often destroyed through ignorance or want of skill. 

Almost any packing may be improved by being soaked in bees¬ 
wax, tallow, and black-lead, before being used. 

Gum-joints that require to be frequently taken apart, should be 
coated with chalk before being placed between the flanges; this 
prevents the gum from adhering to the metal and being destroyed 
when the joint is taken apart. All gum-joints located in the water- 
space of steam-boilers should be coated with black-lead and tal¬ 
low before being put together. This has the effect of preventing 
the sulphur of the gum from attacking the metal and destroying 
the surfaces. 

When it becomes necessary to stop an engine with a heavy fire 
in the furnace, place a layer of fresh coal on the fire, shut the 
damper, and start the injector or pump, for the purpose of keeping 
up the circulation in the boiler. 

Always see that the cylinder drain-cocks are open when the 
engine is standing still, and never close them till after starting. 

Never admit the tallow to the cylinder until the engine is fairly 
under way, and the cylinder drain-cocks closed. 

Always start an engine slowly, and allow it to come up to speed 
gradually. 

Before starting an engine, always warm up the cylinder by ad¬ 
mitting the steam to both ends ; if a marine engine, see that every¬ 
thing is clear of the engines and propeller, and that the cocks and 
valves are all right. 

Whenever an engine is stopped for any length of time, examine 
all its parts, for the purpose of seeing if they are in good order. 

In cases of extreme heating, slack up on the keys and gibs, 
permit them to run loose for a time, and then take up the lost 
motion gradually. 

Examine the piston-packing in the cylinder frequently, for the 
purpose of seeing that it is tight and in good order. 

Keep the cylinder and steam-pipes well covered with some good 




TIIE ENGINEER’S HANDY-BOOK. 


237 


non-conductor, to counteract the cooling effect of the atmos¬ 
phere. 

Whenever a clicking noise is heard in the cylinder, open the 
cylinder drain-cocks,and allow the water to escape; then let them 
remain open until the cylinder works dry steam. 

In giving instructions for the care and management of steam- 
engines, too much stress cannot be laid upon the injunction, “ Keep 
your steam always at the same pressure,” as, although all engines 
employed for manufacturing purposes have governors, they are 
not always reliable or capable of meeting the requirements of 
varying steam-pressures and varying loads; consequently, if the 
steam is, through neglect, permitted to rise above the working 
pressure, the engine will increase its speed, which will induce a loss 
of steam, as every revolution above the speed at which the engine 
was intended to run, and at which the machinery is geared for the 
manufacture of the different materials, is a waste; and every revo¬ 
lution the engine falls below the regular speed is a loss of produc¬ 
tion. 

Piston-Rod and Yalve-Rod Packing, and How to Use it. 

Probably no part of the steam-engine is more frequently out 
of order than the piston-rod and valve-rod packing. This may be 
attributed to various causes, viz., such as the speed of the engine; 
whether it is in line or not; whether the piston leaks or not; the 
condition of the piston-rod; the pressure of the steam ; the clear¬ 
ance in the cylinder, and the character or quality of the material 
of which the packing is composed, as well as the manner in which 
it is applied, and how it is treated afterwards. 

If the engine is out of line, the piston-rod will crowd the pack¬ 
ing to one side or the other at certain points of the stroke; if the 
piston- and valve-rod are badly fluted, the steam will escape through 
the grooves ; if the piston-packing leaks in the cylinder, it will be 
impossible to keep the packing around the rod tight, in conse¬ 
quence of the cushioning induced by the leakage. If the distance 
between the piston and cylinder-head is not sufficient, the steam 


238 


THE ENGINEER’S HANDY-BOOK. 


will escape through the stuffing-box as the engine approaches the 
centres; if the rings of the material are cut too long, they will 
not, when screwed up, hug the rod, and, as a result, leakage will 
occur; if too short, the steam will insinuate itself between them, 
and cause leakage; if the material is not of the proper size to fill 
the cavity between the rod and the box, it will leak, however 
tightly it may be screwed up; if the packing is screwed up too 
tight at first, the heat induced by the friction will soon destroy its 
elasticity, and leakage will be the result; if the engine runs at a 
very high speed, the packing will deteriorate faster than if the 
speed is moderate; and if the pressure is high, the temperature 
due to the pressure will have a tendency to destroy the packing. 
Another cause, and indeed one of the main causes which induce 
leaking around piston- and valve-rods, is the want of depth of the 
stuffing-boxes of some engines, which will not receive more than 
two rings of packing; as a result, they are continually leaking 
around the rod, whereas, if the box is sufficiently deep to admit 
of four rings, the leakage nuisance would be obviated. 

A great variety of materials is in use for packing purposes, 
soap-stone, paper, india-rubber, asbestos, tin-foil, webbing, wire- 
cloth, metallic packing, etc., each of which possesses merit peculiar 
to itself, but, like governors, and many other important adjuncts 
of the steam-engine, not one of them was ever known to answer 
every place, or give satisfaction under all circumstances. This 
arises from the fact that our investigation has not been such up 
to the present time, on this subject, as to enable us to decide which 
material will give the most satisfaction under the most varying 
circumstances ; besides, the best material may be rendered useless 
in a comparatively short time through ignorance, while an inferior 
quality may render good service by being intelligently treated. 

The following instructions may be of use to those who have not 
had much experience in packing piston- and valve-rods: Insert as 
much packing into the box as will just allow the gland to enter; 
then screw it up solid; after which the nuts should be slacked for 
the purpose of allowing the packing to swell when exposed to the 


THE ENGINEER’S HANDY-BOOK. 239 

steam ; if leakage occurs, screw them up gradually and evenly, 
until it stops. If the leakage is excessive, after a sufficient quan¬ 
tity is inserted in the box, do not continue to screw it up, as the 
heat of the rod will soon destroy the packing. It is always better 
to stop the engine, if practicable, remove two or three pieces, and 
replace them again in opposite positions, when in all probability 
the leakage will cease. Never use any old file or any rough in¬ 
strument to remove the packing from the boxes, as they have a 
tendency to abrade or flute the rods, and cause leakage. Every 
engineer and steam-user should provide himself with suitable 
tools for removing the old packing from the boxes and inserting 
the new. To find the proper diameter of the packing for any 
stuffing-box : Measure the diameter of the rod, and also the gland 
or tetem of the stuffing-box, and half the difference between the 
two will be the proper size of the packing. 

Numerous attempts have been made at different times to sub¬ 
stitute a metallic piston- and valve-rod packing for the various 
fibrous packings now in use which would be more durable, and 
at the same time involve no more cost; but up to the present time 
none of these attempts have been crowned with success. This 
may be attributed to various causes, such as the condition of the 
piston-rod, whether it is fluted or not; whether the engine is in 
line or not; the condition of the steam-packing in the cylinder; 
the depth of the stuffing-box, whether it is leaky or not; the 
clearance Space between the piston- and cylinder-heads when the 
crank is at the centre; the amount of back pressure; the difficulty 
of manufacturing the metallic packing in sizes to meet all the 
vagaries of that class of steam-engine builders who pay no atten¬ 
tion to good proportions, and who. make the stuffing-boxes odd 
sizes; the condition and shape of a stuffing-box to which it has to 
be applied; the ignorance displayed in its care and management, 
as well as a disposition on the part of those who have it in charge to 
cry down every new innovation in steam engineering, and to ridi¬ 
cule every adjunct of the steam-engine and boiler that requires any 
special attention, however great a safeguard or economizer it may be. 


240 


THE ENGINEER’S HANDY-BOOK. 


WardwelPs High-Pressure, Yalveless Engine. 

The cut on page 241 represents WardwelPs Valveless Engine. 
As will be observed, it is a horizontal engine, with one end of a 
girder frame bolted to and supporting the cylinder, and the other 
supporting the pillow-block. The pillow-block brasses are pro¬ 
vided with side adjustment wedges, operated from the top face of 
the cap by bolts and nuts. The cross-head has V-shaped bear¬ 
ings, top and bottom, with a wrist-pin providing journal-bearings 
for the fork end of the connecting-rod. The straps at these ends 
of the rod are provided with the ordinary gibs and keys. At the 
crank-pin end, however, the strap is secured to the rod by a bolt 
passing through the strap, the key merely serving to adjust the 
brasses. The piston passes a working fit through the cross-head, 
being secured at each end by jamb-nuts, by which arrangement 
any lateral play of the piston-rod in the cross-head is prevented ; 
but at the same time the rod rotates in the latter. To the ex¬ 
treme end of the piston-rod, after it has passed through the cross¬ 
head, there is keyed fast a section of a bevel-wheel containing 5 
teeth, which gears into another containing 4 teeth; this latter sec¬ 
tion being bolted fast to the inside of one of the fork-arms of the 
connecting-rod; the outside arm being selected as affording the 
best advantages for adjustment. When the connecting-rod is at¬ 
tached to the crank- and cross-head, and steam admitted to the 
cylinder, a semirotary movement takes place in regular order, and 
as the stroke proceeds, the steam passages are so arranged that 
steam can be admitted, cut off, and exhausted at any desired 
point of the stroke. It is obvious, however, that to accomplish 
this the piston-head in the cylinder must be extra long in propor¬ 
tion to the stroke. 

The piston is solid, similar to a plunger, and is a neat working 
fit in the bore of the cylinder. The wear is provided for by the 
insertion at each end of the piston-head of ordinary spring pack¬ 
ing-rings; and to take up wear and prevent leakage from one port 
to the other, a straight, longitudinal, spring packing-piece is placed 



The Ward well Valveless Engine. 


the engineer’s handy-book 


241 



21 



























































































































































































242 


THE ENGINEER’S HANDY-BOOK. 

between the steam passages in the piston-head, thus preventing 
the escape from one port to the other. The steam-port is in the 
centre of the cylinder, and on top. The steam passages in the 
piston-head commence near one end, and run along the circum¬ 
ferential surface, in a longitudinal but curved line, so that the 
passage will remain full open to the cylinder steam-port, notwith¬ 
standing the rotary motion of the piston. At such part of the 
stroke, however, at the point at which the steam is to be cut off, 
the steam passage turns at an angle, and runs round nearly one- 
half the perimeter of the piston-head, so that the rotary motion 
of the piston during the remainder of the stroke is insufficient to 
permit any communication between the cylinder-port and piston 
passages. So soon as the piston-head steam passage turns the 
angle above noted, the longitudinal movement of the piston-head 
past the cylinder steam-port cuts off the supply of steam, and the 
remainder of the piston-stroke is performed by expansion. The 
circumferential direction of the passage above referred to serves 
another purpose than acting as a cut-off, in that it enables the 
same passage to be used to convey the steam to the cylinder ex¬ 
haust-port. After the steam passage has taken the circumferential 
direction referred to, it continues longitudinally to the end of the 
piston-head; the steam passage, while isolated from the cylinder 
steam-port, comes into open communication with the cylinder ex¬ 
haust-port, and that stroke of the engine is completed. For the 
return-stroke, a similarly arranged passage is provided in the 
piston-head, and hence the piston requires but two passages, 
each of which operates alternately, as induction and eduction 
passages. 

There were three of this description of engines on exhibition 
at the Centennial Exposition, which attracted considerable atten¬ 
tion, in consequence of the arrangement for admitting and ex¬ 
hausting steam being entirely different from anything heretofore 
employed. Such engines possess no practical value, their chief 
interest consists in the novelty of the arrangement. 


THE ENGINEER’S HANDY-BOOK. 


243 


Lubricants. 

To understand the quantity of oil required for steam-cylinders, 
slide-valves, and the reciprocating or revolving parts of steam- 
engines, we should first know what its objects are. The object of 
oil is to diminish friction, by interposing a thin film between the 
sliding or revolving surfaces. To insure perfect lubrication, the 
surfaces must be kept coated at all times, under all pressures and 
velocities. In steam-engines there is a sliding and rotating fric¬ 
tion, and it is very doubtful if any one kind of oil is perfectly 
suited to both. Oil has no tendency to improve the character of 
a bearing; its functions being simply to keep them apart, prevent 
heat, and diminish friction. 

Temperature exerts a very important influence over any lubri¬ 
cant. A thin oil has a tendency to run off too fast, while a thick 
one is not sure to flow. Tallow, and all other thick and greasy 
compounds, are exposed to the same objection, as the bearing gen¬ 
erally gets hot before the lubricant begins to flow. Besides, what 
may be called a good lubricant, one that adheres to the rubbing 
surfaces under ordinary circumstances, may not be equally well 
adapted to all conditions, as the area of the bearing surfaces varies 
with the size of the journals, and the form of the boxes, which 
causes a difference in the velocity of rotation. From this, it fol¬ 
lows, that a lubricant that would be retained between the frictional 
surfaces under a light load, would be entirely pressed out under a 
heavy one. 

The quantity of lubrication that the cylinders and slide-valves 
of any engine require, depends on the condition of the engine, the 
amount of work it is performing, and on the pressure and tem¬ 
perature of the steam. If the load is light, the pressure low, 
and the engine in good order, very little lubrication is necessary; 
but if the pressure and speed are high, and the engine is working 
up to its full capacity, the cylinder and valves will require to be 
frequently lubricated. But in no case should an unnecessary 
quantity be used, as it is likely to produce a greater evil than the 


244 


THE ENGINEER’S HANDY-BOOK. 

one it was intended to remedy. A person having charge of steam 
machinery should understand the work each part has to perform, 
the speed at which it runs, and the weight it has to sustain. 
Crank-pins and main-bearings require to be frequently oiled ; but 
the condition of the bearing will determine the quantity of lubri¬ 
cation needed. What is needed in any case is a few drops of good 
oil applied often. It may be safely said that five times the quan¬ 
tity of lubrication is used on the revolving and rubbing surfaces, 
and in the valves and cylinder of steam-engines, which is actually 
necessary. 

According to the general impression, grease or animal oil is a 
preserver of metal; but experience has shown that it is more fre¬ 
quently a destroyer, especially of the cylinders, pistons, and valves 
of steam-engines. The reason of this is, that vegetable and ani¬ 
mal fats and oils contain stearic, megaric, and oleic acids, which, 
when subjected to the heat of high pressure steam, that frees them 
from their base, attack the metal and destroy it. This applies as 
well to oils of vegetable as to oils of animal origin, as fish or 
sperm oil. On removing the heads of steam-cylinders and the 
bonnets of steam-chests, the cylinders, pistons, and steam-chests 
frequently show evidence of corrosion, which differs entirely from 
that of ordinary wear, and which persons unacquainted with the 
nature and effect of the oil and grease they have been using, are 
puzzled to account for. Oils derived from petroleum contain no 
oxygen, cannot form acid, and therefore do not attack metal. 
The proof of this may be found in the fact, that such oils are used 
in surgical operations, and for cuts, bruises, and abrasions, with 
good effect. Oils from petroleum are produced for nearly every 
mechanical process, as well as for the cylinders of steam-engines, 
for which latter purpose animal oils were considered indispensable. 

At a recent meeting of the Railway Master Mechanics’ Associ¬ 
ation, at St. Louis, a report was presented by the committee on 
lubricants, which embodied the result of a series of experiments 
made for the purpose of testing the lubricating qualities of differ¬ 
ent kinds of oil. In making the test, 56 drops of each variety 


THE ENGINEER’S HANDY-BOOK. 


245 


of oil were put into a dynamometer, which was run at 35 miles 
an hour, until the temperature was raised from 60° to 200° Fall. 
The exact number of revolutions necessary to produce this change 
of temperature was noted in each case, and is given in the last 
column of the following table. 


Description of Oil. 

Cost per 
Gallon. 

Average Rev¬ 
olutions. 

Castor Oil. 

$1.25 

12-946 

Paraffine. 

.28 

11-685 

Mecca (black). 

.45 

9-982 

Manufactured "A” . 

.35 

9-653 

« « 

.90 

9-394 

(C u «< (J» 

.25 

9-187 

Neat’s-foot. 

.85 

8-277 

W. Virginia. 

.26 

7-915 

Sperm. 

1.75 

7-912 

Tallow . 

.70 

7-794 

No. 1 Lard. 

.70 • 

7-377 

Manufactured “D” .... 

.25 

6-999 

U « » p 1 ” 

.85 

6-798 

tc a “JP” 

.20 

6-121 

W. Virginia (reduced) . . . 

.20 

4-770 

Grafton (treated). 

.20 

4-215 


It has lately been demonstrated that natural petroleum oils, 
when thoroughly freed from grit, are for many purposes as good, 
if not better, than sperm, with the advantage of being much 
cheaper; but they are objectionable in consequence of their lia¬ 
bility to stain bright work or finished machinery. 

It is not by any means uncommon to see ignorant and inex¬ 
perienced persons who have charge of steam-engines pouring oil 
on cross-head guides and piston-rods every five minutes during 
the day. This is immediately rubbed off by the shoes or the 
piston-rod packing, without rendering any service, which is a 
wilful waste of the necessary supplies in their charge, and has a 
tendency to lessen the profits of the establishment. 

21 * 















246 


THE ENGINEER^ HANDY-BOOK. 


Questions: 

THE ANSWERS TO WHICH WILL BE FOUND IN THE TEXT. 

What are the objects and functions of the bed-plate as a part 
of the steam-engine ? 

Give the rule for finding the necessary strength of a bed-plate 
for any given speed and pressure. 

State the rule for finding the proper thickness of a steam-cyl¬ 
inder of any diameter. 

Give the rule for finding the diameter of a cylinder for any 
given horse-power. 

Give the rule for finding the cubic contents of a steam-cylinder 
of any given diameter. 

State the rule for finding the quantity of steam that any engine 
will use at each stroke of the piston. 

Give the necessary strength of cylinder-head bolts. 

What are the objects and functions of the pistons of steam- 
engines, and what qualities should they possess ? 

Give the proportions of piston-rods for condensing and non¬ 
condensing engines, according to the best modern practice. 

Give the units of horse-power for various piston speeds. 

Give the proportions of steam- and exhaust-pipes according to 
the best modern practice. 

What proportion should the diameter of the valve-rod bear to 
that of the cylinder? 

Give the proper length and width of the cross-head bearings. 

What is the meaning of the term eccentric? 


THE ENGINEER'S HANDY-BOOK. 


247 


What are the functions of the crank, and what change of mo¬ 
tion does it induce? 

Explain the cause of the variation of the piston in the cylinders 
of steam-engines when their cranks are at half-stroke. 

Give the rule for finding the position of the piston in the cyl¬ 
inder when the crank is at half-stroke. 

Is there any loss of power incurred in the employment of a 
crank as a mechanical device for converting reciprocating into 
rotary motion ? 

Give the rule for finding the necessary proportions of crank- 
pins for any engine. 

Give the proportion of the crank-shaft and main-bearings ac¬ 
cording to the best modern practice. 

Give the proper proportions of gibs, keys, and straps for any 
engine. 

Why is the strap thicker at the slot than at the part which en¬ 
circles the box ? 

What are the functions of the link? 

What is the meaning of the term “ radius of the link ” ? 

Describe the mechanism of the various links employed as a 
reversing-gear for steam-engines. 

What is the object of the fly-wheel ? 

Give the rule for finding the proper weight of fly-wheel for any 
engine, speed and pressure being given. 

What are the functions of the steam-engine governor? 

Give the rule for finding the proper size of governor-pulleys. 


248 the engineer’s handy-book. 

Give the most approved method of counterbalancing the re¬ 
ciprocating parts of steam-engines. 

What are the most common causes of heating in the journals 
of steam-engines? 

What are the uses and functions of the slide-valve? 

Explain the advantages and disadvantages of the slide-valve 
as contrasted with those of other forms. 

Explain the action of poppet- or conical-valves. 

What are the meanings of the terms lap and lead on the valve? 

What is the meaning of the term loss of lead t 

What is meant by the terms valve-seat and valve-face? 

Explain the meaning of the terms valve-circle and valve-stroke. 

How would you proceed to ascertain the amount of lap and 
lead on a slide-valve without opening the steam-chest? 

Give the meaning of the term cut-off, and the amount of lap 
required to cut-off at different points of the stroke. 

State the most economical point in the stroke at which to cut 
off the steam, and demonstrate it by an example. 

What is meant by friction when applied to slide-valves? 

How would you proceed to set the valves of a steam-engine? 

Is the friction of a perfectly fitting slide-valve more or less than 
that of an imperfectly fitting one? 

Give the names of the different valves and valve-gear employed 
for the admission and escape of the steam to and from tile cyl¬ 
inders of steam-engines. 


THE ENGINEER’S HANDY-BOOK. 


249 


Give the technical terms as applied to the valve-gear of steam- 
engines. 

Give the names of the various valves and cocks in use on dif¬ 
ferent steam-engines and boilers. 

Give the names of the various pipes in connection with differ¬ 
ent kinds of steam-engines. 

Explain the meaning of the term valve-gear. 

In what condition should an engine be kept? 

What is the best evidence of an engineer’s capabilities ? 

What dependence should be placed on patent oil-cups? 

In what condition should the packing in the piston- and valve- 
rod boxes be kept ? 

What is the objection to striking any part of an engine with 
the face of a hammer or head of a monkey-wrench? 

What is the objection to placing piston-rod packing or cotton 
waste on the floor ? 

When should piston- and valve-rod packing be applied? 

In what manner may piston- and valve-rod packing be improved? 

How should gum-joints be treated, which must of necessity be 
frequently broken ? 

What precaution should an engineer take, when it becomes 
necessary to stop an engine with a heavy fire in the furnace? 

How should the cylinder drip-cocks be kept, when an engine is 
stopped ? 

When should the tallow or any other lubricant be admitted to 
the cylinder? 


250 


THE ENGINEER’S HANDY-BOOK. 


How should an engine be started ? 

What precaution should an engineer take before starting an 
engine? 

What course should an engineer pursue when it becomes neces¬ 
sary to stop for any length of time? 

What course should be adopted in case of extreme heating in 
any of the revolving parts of an engine? 

How should the piston-packing in the cylinder be treated? 

What are the best means of protecting the cylinder and steam- 
pipes from the effects of the atmosphere in order to diminish 
radiation and condensation? 

What course should be adopted when a clicking sound is heard 
in the cylinder? 

Why is it very important that the steam pressure should be 
kept uniform ? 

Give the reasons why the piston- and valve-rod packing is so 
frequently out of order. 

Explain the best method of using piston- and valve-rod packing. 

What is the best course to adopt when excessive leakage oc¬ 
curs? 

How should piston- and valve-rod packing be kept? 

Give the rule for finding the right diameter of packing for any 
stuffing-box. 

What is the object of lubrication? 

What effect has temperature on lubricants? 

What conditions influence the amount of lubrication required 
for any engine ? 


THE ENGINEER^ HANDY-BOOK. 


251 


PART FOURTH. 


The Steam-Engine Indicator: Its Invention and 

Improvement. 

Perhaps no device, in the entire range of mechanical inventions, 
has aided so much in developing and perfecting the steam-engine 
as the indicator. 

This arises from the 
fact that no other in¬ 
vention yet brought 
forward pertaining 
to the science of 
steam engineering 
can read the inner 
workings of a steam- 
engine, point them 
out with unerring 
accuracy, and dis¬ 
cover the sources of 
waste in it. Conse¬ 
quently, its import¬ 
ance cannot be too 
highly estimated, 
and its use too much 
encouraged and ex¬ 
tended in all classes 
of steam-engines. 

The steam-engine indicator is said to have been invented by 
James Watt, which is rather doubtful; and, as Watt received 
credit for many things he never invented, it is not to be won¬ 
dered at that the invention of the indicator has been attributed 
to him. Be that as it may, Watt’s indicator, though very im- 



































































































252 


THE ENGINEER’S HANDY-BOOK. 


perfect, answered for engines travelling at a piston speed of about 
150 feet per minute, and for pressures averaging 7 lbs. above 
atmosphere, which he thought was the fastest speed and the highest 
pressure that would ever be needed. But experience soon demon¬ 
strated that the highest economy was attained with high piston 
speeds and correspondingly high pressures, and, as a result, 
Watt’s indicator proved to be unsuitable for these conditions. 
The requirements of such an instrument were more fully appre¬ 
ciated by McNought, of Glasgow. The world is more indebted 
to him for improvements in the steam-engine indicator than to 
any one previous to his time. 

The indicator was further improved by Hopkinson, Stillman, 
and others; but these improvements were not in the mechanical 
design or arrangement of its working parts, but rather in the 
accuracy and refinement of the workmanship employed in its 
construction, as the mechanical principles embodied in the Watt 
indicator were continued in them all. They consisted of an up¬ 
right cylinder, into which a piston was accurately fitted. To the 
piston-rod a spiral spring was attached, to resist the steam and the 
vacuum when acting against it. The pencil was also attached to 
the piston-rod ; the result of which was that the piston, piston-rod, 
and spring had the same movements as the pencil. With such 
instruments the vibration of the piston was so great as to render 
them totally unreliable with fast running engines, or when steam 
was worked expansively. 

Gooch was the first inventor that gave the pencil a greater 
range of movement than the piston. In his instrument the cyl¬ 
inder was placed horizontally, and when its piston was subjected 
to pressure it compressed two elliptic springs. The top of his 
piston-rod was connected to the short arm of a lever, to the long 
arm of which the pencil was attached, thus giving considerably 
more motion than could be obtained by any former instrument. 
The pencil moved in the arc of a circle instead of a straight line. 
The diagram was traced on a web of paper while it was unwound 


THE ENGINEER’S HANDY-BOOK. 


253 


from one drum and wound upon another. This arrangement ad¬ 
mitted of a succession of diagrams being taken without any in¬ 
termediate manipulation of the instrument. The communication 
between the indicator and 
the steam-cy 1 inder was closed 
by a slide-valve instead of a 
cock. But as the principle 
of working steam expan¬ 
sively became almost uni¬ 
versal, an instrument more 
reliable than any of these 
previously mentioned be¬ 
came a necessity of the 
times, and such was found 
in the Richards’ Indicator. 

In this instrument the fol¬ 
lowing construction and pro¬ 
portions have been adopted, 
and adhered to from the 
first. The area of the piston 
h J a square inch, the di¬ 
ameter of which is very 
nearly of an inch, or, 
more exactly, *79 inch. The 
length of the long arm of 
the lever, to which the rod 
of the piston is attached, is 
3 inches, and the distance 
from the pivot of the lever 
to the point of attachment of the piston is f of an inch, thus giv¬ 
ing the free end of the lever, and with it the pencil, four times 
the movement of the piston. The secondary lever is equal in 
length to the first, and the link which connects the two, and which 
carries the pencil at its centre, is TJ inches long. These propor- 
22 



Section of the Indicator. 







































































































































































































254 


THE ENGINEER’S HANDY-BOOK. 


tions give a practically straight pencil movement for a distance 
of 2? inches. 

As the tendency of the times for the past 15 years has been to 
regulate the flow of steam from the boiler to the cylinder auto¬ 
matically instead of by throttling, it became manifest to engineers 
that an instrument that would take faithful diagrams from fast¬ 
running engines, particularly those in which the change of pressure 
and work are necessarily great, was one of the necessities of the 
age. Such a want was supplied by J. W. Thompson, of Salem, 
Ohio. In Thompson’s Indicator, a cut of which may be seen on 
page 251, the parallel movement which carries the pencil is re¬ 
duced in weight, until jts momentum is scarcely one-third as great 
as that of any former instrument; as a consequence, the difficulty 
so frequently experienced in taking cards with previous indicators 
from fast-running engines, particularly those of the automatic cut¬ 
off class, owing to the vibration of the pencil, was obviated, and a 
much neater construction obtained. 

The indicator was further improved by Harris Tabor, (cuts 
of whose instrument may be seen on pages 260 and 261;) but the 
most improvements heretofore made in the indicator have been 
effected by George H. Crosby, a distinguished mechanic and in¬ 
ventor of Boston, Mass. It has seemed to be the aim of Mr. 
Crosby to avoid unnecessary weight in the reciprocating parts, to 
insure correctness of action, and to so simplify the method of manip¬ 
ulating the instrument as to bring it within the understanding of 
engineers of limited education and persons of ordinary intelli¬ 
gence. In these objects he seems to have been eminently successful, 
as the Crosby Indicator is an improvement, in many respects, on 
all other devices of the kind in use; as it is perfectly reliable in 
its recordings, whether employed for taking diagrams from auto¬ 
matic cut-off', throttling, simple, compound, fast- or slow-running 
engines; as it is free from some very objectionable features in 
other instruments, which render the diagrams taken by them 
erroneous. In the conception of this instrument, the inventor 


THE ENGINEER’S HANDY-BOOK. 


255 



seems to have predetermined all the circumstances, emergencies, 
and requirements 
that could possibly 
arise in the use of 
the indicator, and 
provided for them. 

Its working mech¬ 
anism will be easily 
understood from the 
following descrip¬ 
tion and explana¬ 
tion : 

A is a case or 
jacket enclosing a 
cylinder, into which 
a piston is nicely 
fitted to move with¬ 
out friction; to the 
upper side of this 
piston is attached a 
steel helical spring, 
the upper end of 
which is fastened to 
the cap or head of 
the cylinder; to the 
upper end of the 

piston-rod, B, is di- . 

r . . Crosby s Improved Indicator, 

rectly jointed the 

short lever, CD, whose short end is jointed to the head of a vi¬ 
brating standard at D, and its long end is jointed to the long 
lever, E F, at the point C. The long arm of the lever, E F, is 
jointed at its outer extremity to a second vibrating standard at 
E, and to the other extremity is attached the pencil F. To the 
case A is permanently attached the horizontal plate G, at one end 




































































256 


THE ENGINEER’S HANDY-BOOK. 


of which is jointed a corresponding plate H, situated above the 
former, and carrying the revolving drum, covered by the paper 
cylinder I. To this drum is attached a cord, wound around a 
groove at its base, and carried by the guide-wheel K between the 
two extra guide-wheels L and M ; the guide-wheels L and M are 
attached to the arm N, which swivels around a point in line with 
the axis of the guide-wheel K, and is held in its proper position 
by the thumb-nut 0. The drum carrying the paper cylinder I is 
rotated in one direction by the tension on the cord, and in the re¬ 
verse direction by the reaction of a spring enclosed therein; the 
tension upon this spring may be adjusted to suit by the thumb- 
nut at the open end of the drum. The plate H carrying the 
drum and paper cylinder is held away from the pencil F by a 
spring, situated between the plates H and (x, directly in line with 
the axis of the drum, until the operator desires to take a diagram. 
By pressing upon the handle P, the paper cylinder is moved for¬ 
ward, and the pencil comes in contact with the paper. Immedi¬ 
ately upon removing this pressure, the paper cylinder automatically 
resumes its former position. Two adjustable stops determine the 
amount of this motion, and regulate the force with which the 
pencil presses upon the paper, a hair-line being attainable without 
friction. The bushing which carries the pencil is bored to re¬ 
ceive a graphite or metallic wire, and is supplied with means for 
holding it in any position desired. The piston-rod is bored at 
each end, almost half its length, leaving a thin partition or stop 
in the centre; the upper chamber is used as a reservoir for a lu¬ 
bricant, and is provided with pin-holes close to the partition to 
allow the oil to flow in and down, and so lubricate the rod and 
piston; the lower chamber allows the steam to enter and warm 
the lubricant, causing it to assume a more limpid form and flow 
freely in cold weather. The piston-rod is thus made lighter, with¬ 
out weakening it materially. A minute portion of felt placed at 
the bottom of the reservoir will prevent the oil from flowing too 
readily. It can be filled at the cross-head with a few drops of oil, 


THE ENGINEER’S HANDY-BOOK. 


257 



by using a common pressure-oiler with a very small nozzle. To 
adjust the pencil to the proper position for springs of different 
scales, the head of the 
piston-rod is provided 
with a screw-threaded 
pin and lock-nut, by 
means of which the 
pencil may be made to 
assume any desired 
height. The use of a 
revolving drum for 
transmitting motion to 
the paper having been 
demonstrated to be the 
best means for the pur¬ 
pose, it has been adopt¬ 
ed ; the prerequisites be¬ 
ing sufficient strength 
of spring and inelastic¬ 
ity of cord to overcome 
the momentum of the 
reciprocating parts. By 
substituting the left- 
handed guide-wheel 
arm (which is supplied) 
for one on the instru¬ 
ment, and simply ad¬ 
justing the drum, drum¬ 
spring, and cord so as 
to run in the reverse di¬ 
rection, this indicator 
may be made to work 
left-handed without any 

further change. Section of Crosby’s Indicator. 

22* R 


































































258 


THE ENGINEER’S HANDY-BOOK. 


The greatest degree of accuracy and excellence is maintained 
in the manufacture of this indicator, and no pains are spared to 
make it the most reliable instrument for the purpose in use. To 
adapt the indicator to any pressure, springs are made of the fol¬ 
lowing scales: 

Nos.— 8,12, 16, 20, 24, 30, 40, 50, 60, 80, 100. 
Lbs.— 24, 36, 48, 60, 70, 90, 120, 150, 180, 240, 300. 

The number of the springs represents the pounds per square inch 
required to compress it sufficiently to move the pencil vertically 
one inch on the diagram. The figures in the lower line designate 
the maximum pressure of steam, or steam and vacuum, for which 
the spring is adapted, and which, when taken together with the 
space allowed at each end of the stroke for adjustment, equals the 
whole distance that the pencil cau travel. 

The advantages of the Crosby Indicator are, that the parallel 
motion is not a geometrical approximate imitation of, but a true 
motion ; that the motion of the pencil is a uniform multiplication 
of the piston of the indicator, and is solely controlled by the mo¬ 
tion of the piston-rod; and that there are no guiding-slots, either 
straight or curved, to induce friction; that there is no compensat¬ 
ing arm jointed to any fixed point, as in other indicators; that the 
pencil is located close to the piston-rod, instead of projecting several 
inches to one side, as in other cases; that an air-chamber or jacket 
surrounds the steam-cylinder instead of a steam-jacket, as in other 
instances; that the piston-rod is hollow instead of solid, and that 
it is solidly united to the piston, thus requiring no joints below' 
the cap, which obviates the possibility of corrosion by the action 
of the steam or moisture; that there is no link or connecting-bar 
between the head of the piston-rod and lever to cause friction or 
inaccuracy of motion ; that the cylinder, piston, and piston-rod 
are automatically oiled by a self-lubricating device, thus removing 
the possibility of friction, which always induces error in the re- 


THE ENGINEER’S HANDY-BOOK. 259 

cordings of the indicator, thus rendering the diagram deceptive 
even to experts ; that, wherever possible, every joint is made with 
steel pivots instead of journals, as is the case in other instruments; 
that the mechanism for adjusting each instrument is so arranged 
that it may be used either left- or right-handed, as the case may be, 
in order that diagrams may be taken from either end of the cyl¬ 
inder without the necessity of two indicators; that means are 
provided for adjusting the distance that the paper shall move 
towards the pencil, so that a hair-line can be drawn without fric¬ 
tion ; that the reduction in weight in the piston and hollow piston- 
rod and the refinement of workmanship in the levers and joints, 
render the reciprocating parts so extremely light that momentum 
and friction are reduced to a minimum; that it is more easily ad¬ 
justed and operated than any other instrument of the kind ever 
heretofore invented, thus dispensing with the necessity of experts, 
and that diagrams may be taken from each end of a steam-cylin¬ 
der without the least difficulty, even by engineers of ordinary in¬ 
telligence and limited experience, from engines running at the 
highest practicable piston speed. 

They are manufactured by the Crosby Steam Gauge and Valve 
Co., Boston, Mass. 


Tabor’s Indicator. 

The cuts on pages 260, 261, represent Tabor’s Steam-Engine 
Indicator. — As will be observed, its most striking features are its 
parallel motion and the plainness of its cylinder. The piston has 
a single capillary packing groove, and its whole action is remark¬ 
ably nice. The springs, both as to range and general structure, 
are similar to those in the Richards and Thompson Indicator. It 
will be noticed that the piston-rod, which is jointed to the piston 
and the pencil-lever, is slotted ; this slot is curved, and works 
over a guide-roller set in the cylinder-cap. The rear end of the 


260 


THE ENGINEER’S HANDY-BOOK. 


pencil-lever is pivoted to the radius link. The slot-curve is that 
peculiar curve which would be described by the guide-roller as a 
scribing point while the pencil is being moved in a true line; 
this, it is claimed, insures a correct parallel motion to the pencil. 
The guide-roller is journalled in a free collar held in the cylinder- 

cap, which allows 
all the moving parts 
to revolve freely, as 
the pencil is brought 
in contact with the 
paper. 

The paper drum 

revolves on a steel 
spindle, upon which 
the bottom nut is 
screwed; the nut 
inside the drum is 
si mpiy a m i 1 led head 
firmly screwed on 
the upper end of the 
spindle. The recoil¬ 
spring is seated in a 
cup on the bracket, 
the outer end being 
fixed to it, while the 
inner end is hooked 
by the hub on the 
drum-base. A stop- 

block on the cup, engaging with a lug in the drum-base, forms the 
stop for the recoil motion. If the spindle be slacked somewhat, 
the drum-base may be revolved over the stop-block, and more or 
less tension given to the recoil-spring. By simply unscrewing the 
cylinder-cap, the whole motion work may be removed in one 
piece. The pencil-lever, piston-rod, and radius-link, are all of steel, 



Tabor’s Indicator. 

















































































THE ENGINEER^ HANDY-BOOK. 


261 


spring tempered; the 
small number of 
moving parts, and 
their lightness, re¬ 
duce the error of 
momentum that ex¬ 
ists in instruments 
of heavier parts, 
which is frequently 
a source of uncer¬ 
tainty. The whole 
instrument is very 
light, the design sim¬ 
ple, and the work¬ 
manship neatly done. 

It is claimed that the 
diagrams produced 
are very good. 

Functions of the Indicator. 

The function of the indicator is to automatically trace out on 
paper a diagram that will graphically represent the pressure of 
the steam in the cylinder of the engine to which it is attached, with 
all its variations during both forward and return strokes of the 
piston. It enables those who use or have charge of steam-engines, 
to ascertain the condition of the parts of the engine subject to 
the direct action of the steam, and to what advantage the steam 
is applied; whether the valves are properly designed and ac¬ 
curately set, and if the steam-passages or ports are of the proper 
size to receive and discharge the steam in time to produce the best 
effect; what pressure of steam there is upon the piston at every 
position in the cylinder, as well as its average during the stroke; 
what is the value of the vacuum acting upon the piston of a con¬ 
densing engine in all its positions in the cylinder, and what is its 



Section of Tabor’s Indicator. 





























































262 


THE ENGINEER^ HANDY-BOOK. 


average; whether the exhaust passages from the cylinder are 
sufficiently large to give free exit to the steam, and, if not, what 
percentage of power is lost in forcibly expelling it; the actual 
consumption of steam in giving motion to the engine, and also 
what additional steam is used in giving motion to the shafting 
and millwark, the paddle-wheel or screw-propeller; and also what 
power is required to move the machinery, or any part of it. 

In manufacturing establishments where power is let to tenants 
it will show how much is consumed by each, and it will also dem¬ 
onstrate the degree of economy in using steam at different press¬ 
ures, the benefits of expansion, and the relative efficiency of 
different kinds of expansion-gear. 

Indicator cards are of great value, as they demonstrate the 
initial, mean effective, and terminal pressures, the back pressure, 
the cushion, whether by compression or lead ; the point of cut-off, 
and the relative economy of different engines, aside from leakage 
and condensation. It may be applied not only to steam-engines, 
but to those driven by compressed air, or any vapor or fluid, as 
well as to the cylinders of air-pumps, air-compressors, blast-engines, 
etc. The diagram produced is the joint production of two move¬ 
ments, viz., a vertical movement of the marking point due to the 
pressure of the steam acting on the piston of the instrument, in 
opposition to the force of a spring of known strength, and a hor¬ 
izontal movement of the paper, as the drum, on which it is placed, 
makes partial rotations to and fro coincident with the movement 
of the piston. Hence, when the pencil is held in contact with the 
paper during one revolution of the engine, both will aVrive at the 
point from which they started at the same moment, and a closed 
figure will be the result, except when a great change in the load 
and pressure occurs during the stroke in which the diagram was 
taken. 

The value of indicator diagrams is that they show what propor¬ 
tion of the boiler pressure is contained in the cylinder; how early 
in the stroke the highest pressure is reached ; how well it is main¬ 
tained ; at what point and at what pressure the steam is cut off; 


263 


THE ENGINEER’S HANDY-BOOK. 

whether it is cut off sharply, or in what degree it is wire-drawn; 
at what point, and at what pressure it is released; whether it is 
freely discharged, or what proportion of it (in excess of the atmos¬ 
phere or the vacuum in the condenser, according as the engine is 
condensing or non-condensing) remains to exert a counter or back 
pressure; whether, before the commencement of the stroke, there 
is any compression of the vapor remaining in the cylinder, and if 
so, at what point in the stroke it commences, and to how high a 
pressure it rises. The foregoing particulars can only be learned 
by observation, though a scale, corresponding with the spring used, 
is needed to measure the pressures, and to locate the exact events 
in the stroke. The points to be observed in estimating diagrams 
are, the mean or average pressure; the total mean, or the mean 
effective pressure; the indicated horse-power, I. H. P., and the 
theoretical water consumption. The indicator shows the pressure 
at each and every point in the stroke; to represent this faithfully 
is its sole office. The causes which determine the form of the 
figure must be determined by the engineer. 

Technical Terms Used in Connection with the Employ¬ 
ment of the Indicator. 

The term Adiabatic literally means no transmission. As applied 
to an expansion curve, it means that it correctly represents at all 
points the pressure due both to the volume and the temperature, 
just as if no transmission of heat to or from it had taken place. 

Admission. —This term is applied to the induction of the steam 
into the cylinder when the valve opens at the commencement of 
the stroke. 

The term Asymptote means a line which approaches nearer and 
nearer to some curve, but which, though infinitely extended, would 
never meet it. The clearance and vacuum lines of a diagram are 
asymptotes of a true expansion curve. 


264 the engineer’s handy-book. 

The letter b at the end of a diagram means that that end was 
taken from the bottom end of the cylinder. 

A. B. or Aba. is understood to stand for above atmosphere, and 
B. A. or Bla. below atmosphere. 

The term Compression is a term used to express the distance 
through which the piston moves in the cylinder after the exhaust 
has closed. Compression takes place between the piston and the 
cylinder-head at the end of each stroke; and the distance from the 
end of the cylinder at which it takes place depends on the amount 
of lap on the valve. 

The term Cushion means the resistance offered on the opposite 
side of the piston induced by the steam shut up in the cylinder. 

Cylinder efficiency. —This term is used to designate the amount 
of work performed in the cylinder of a steam-engine for a given 
pressure. 

The term Clearance is used to express the extent of the space 
which exists between the piston, the cylinder-head, and the valve- 
face at each end of the stroke. See page 122. 

Displacement. — This term is applied to the cubic contents, or 
the volume of water, steam, or air displaced by the piston during 
one stroke. It may be found by multiplying the area of the piston 
in inches by its stroke in inches. The product will be its displace¬ 
ment in cubic inches. 

Duty. — This term is understood by engineers to mean the effi¬ 
ciency of steam-engines, or the number of pounds that an engine 
is capable of raising one foot high per second with an expenditure 
or consumption of one hundred pounds of coal. 

The term Flexure means bending or curving. The point of 
flexure in a diagram is the point at which the cut-off closes and 
the expansion curve begins, as shown at C, explanatory diagram 


THE ENGINEER’S II ANDY- BOOK. 265 

No. 1, page 291. The point of contrary flexure is the point at 
which the line changes its direction by curving outwards and 
afterwards inwards, as shown at A, on diagram on page 291. 

H. P. cyl. stands for high-pressure cylinder. 

H. P. means horse-power, which, when applied to the steam- 
engine, means 33,000 lbs. raised one foot high ; or 150 lbs. raised 
220 feet high; or 550 lbs. raised one foot high in one second. 

The term Hyperbola means a plane figure which is formed by 
cutting a portion from a cone by a plane, parallel to its axis or to 
any plane within the cone, which passes through the cone’s vertex. 
The curve of the hyperbola is such, that the difference between 
the distances of any point in it from two given points is always 
equal to a given right line. 

The term Isothermal means uniform or same temperature. As 
applied to an expansion curve, it means that such a curve repre¬ 
sents correctly the expansion or compression of the steam when 
the temperature is uniform. 

L. P. cyl. means low-pressure cylinder. 

The term Ordinates means the vertical lines drawn across dia¬ 
grams to facilitate the calculation of their power. See diagram 
on prtge 291. 

The term Parallelism is generally employed, where two or more 
straight lines may be extended indefinitely, without any tendency 
to approach or diverge from one another. See atmospheric and 
vacuum lines on indicator diagrams. 

Release. —This term is understood to mean exhaust. Resid¬ 
uary exhaust is that which follows the first release of the terminal 
pressure, The term negative exhaust is sometimes used, though 
not generally understood in its literal sense. It means compres¬ 
sion or cushion, and absolutely amounts to the same thing, as it is 
23 


26G 


THE ENGINEER’S HANDY-BOOK. 


merely an early product of the exhaust, for the purpose of retain¬ 
ing a portion of steam in the cylinder as the crank approaches 
the centre of the stroke. 

Rev. or Rev’s is understood to mean revolutions per minute, 
though rspm is sometimes used. 

I. H. P. means indicated horse-power. It means the number 
of H. P. of energy shown by the diagram of an engine, as found 
by multiplying together the area of the piston in square inches, 
its speed in feet per minute, and the mean effective pressure shown, 
and dividing the product by 33,000. 

N. H. P. means nett horse-power, which is the I. H. P. minus 

the friction of the engine. 

The term Initial pressure is generally understood to mean the 
pressure represented in the cylinder between the opening of the 
steam-valve and the closing of the cut-off. More properly speak¬ 
ing, it is the pressure represented in the cylinder at the commence¬ 
ment of the stroke, as the pressure frequently falls considerably 
before the closing of the cut-off. 

M. E. P. means mean effective pressure. It is simply the 

amount by which the average impelling pressure exceeds the 
average resisting or counter-pressure. The M. E. P. on the piston 
of a steam-engine is the measure or exponent of the work per¬ 
formed. 

The term Terminal pressure means the pressure at which the 
steam is exhausted from the cylinder, and may be said to be the 
exponent of the consumption of water by the engine. 

The term Pipe diagram is applied to diagrams taken from the 
steam-pipe for the purpose of determining how much of the press¬ 
ure of the steam in the pipe is lost in passing through the steam- 
ports to the cylinder. 


THE ENGINEER’S IIANDY-BOOK. 


267 


The term Scale menus the number of pounds of steam per 
square inch (acting on the piston of an engine) represented by 
each inch of vertical height on the diagram. Thus a 40 lb. scale 
means that each inch on the diagram represents 40 lbs. of steam 
per square inch, and so on. 

The term Spring means the spring which is employed on the 
piston of the instrument, in order to resist the pressure of the 
steam and the vacuum. The following table will give the limit 
of pressure in the cylinder to which each spring may be subjected. 
The length of each spring given in the third column is such that 
each of them would be extended (when subjected to a perfect 
vacuum) to a length of 2 T 7 g inches, which is the approximate 
length which would carry the pencil to the lower limit of the 
range of movement above given. 


Scale of 
Spring. 

Limit of 
Cylinder- 
Pressure 
above At¬ 
mosphere. 

Length of Spring. 

15 lbs. per in. 

25 lbs. 

2*192 ins. == nearly 24 ins. 

20 “ 

38 “ 

2*255 “ =a little above 21 “ 

30 “* “ 

64 “ 

2*315 “ == “ “ 2y\ “ 

or nearer 2 T 5 g “ 

40 “ 

90 “ 

2*345 “ = nearly 2-/ 0 “ 

60 “• 

143 “ 

2*376 “ —a little over 2| “ 

80 “ 

195 “ 

2*391 “ = a little above 2-| “ 


To find the corresponding limit for grades not given, multiply 
the total range of movement, 2*625 inches, by the scale of the 
spring, and deduct the pressure of the atmosphere. 

Example. — Suppose it is desired to find the limit of pressure for 
a 50 lb. spring: 50 X 2*625 — 14*7 = 116*55. 

The term String, as used in these pages, means the aggregate 
length of the ordinates of an indicator diagram. 

















268 


THE ENGINEER’S HANDY- BOOK. 


The letter T on a diagram denotes that that end was taken from 
the top end of a cylinder. 

The term Undulating means rising and falling, wavy. See 
dotted line on diagram No. 16, page 303. 

Wire-drawing. — This term is applied to the common method 
of regulating the flow of steam from the boiler to the cylinder, 
by throttling or forcing the steam to ooze through some small or 
intricate device, such as the governor-valve, thus tending to destroy 
its elastic force. 

The term Zero, when applied to indicator diagrams, means a 
vacuum. 

How to Attach the Indicator. 

Since it is of the first importance that the diagram should be 
correct, both as to its vertical and horizontal measurements, too 
much care cannot be taken in making the attachments. The best 
method of attaching the indicator to the engine is to drill and 
tap into the cylinder directly opposite the ports. When practi¬ 
cable, the holes should be located exactly at the centre of the 
clearance, or the space between the piston and the cylinder, when 
the crank is at the dead-centre; since, if the holes are bored in 
any part of the cylinder which is travelled over by the piston, the 
communication with the indicator will be closed at that point in 
each stroke. Care must also be taken that they are not too close 
to the cylinder-heads, as the projecting parts of the latter may 
interfere with the free flow of the steam between the cylinder and 
the indicator. But if such a difficulty should arise, recesses must 
be cut in the cylinder-heads, in order to establish the communi¬ 
cation. If the heads can be removed for the purpose of locating the 
holes, it is always best to do so, as their exact location can be de¬ 
termined with perfect accuracy. 

If circumstances will not admit of the holes being drilled into 
the clearance, they may be put in the heads; and, if it is not in- 


THE ENGINEER^ HANDY-BOOK. 


269 


tended to place the instrument in connection with both ends of 
the cylinder at the same time, this location is preferable. It is 
claimed by many engineers that reliable diagrams cannot be ob¬ 
tained, when the pressure has to be transmitted through a long 
pipe, as is the case when the instrument is connected to both ends 
of the cylinder. But it has been shown by experiment, that if 
the cylinder is tapped instead of the heads, thereby using the 
shortest pipe, and the stop-cocks are placed as near as possible to 
the instrument, the difference between diagrams so taken, and 
those taken from a direct attachment, is not always noticeable. 
If, instead of two stop-cocks, one on each side of the instrument, a 
threeway cock be placed under it, which will allow steam to be 
admitted from either end through the same plug, the difference 
can hardly be detected. If no such cock can be had, straight way- 
cocks of ample aperture, placed as close to the L or T, to which 
the instrument is attached, as possible, will give sufficiently satis¬ 
factory results for all ordinary purposes. When, however, it is 
decided to take the diagrams separately, two cocks become neces¬ 
sary, and the card must also have two loops or hooks, as far apart 
as the two positions which the instrument is to occupy. Then it 
may be quickly shifted from end to end as desired. If two in¬ 
struments are attached to an engine, diagrams may be taken 
simultaneously from both ends; but, while such an arrangement 
obviates the difficulty of equalizing the events of the two ends 
with one instrument, it is open to the objection that, if there is any 
difference in the action of the two instruments, or in the strength 
of their springs, this circumstance will interfere with the com¬ 
parison. 

Motion of tlie Paper Drum. 

Owing to the almost endless variety of engines, their peculi¬ 
arities of design, etc., it is impossible to give very definite instruc¬ 
tions which will be applicable to all cases. But it must be borne 
in mind, that the motion of the paper drum must be coincident 
with that of the piston in respect to its times of stopping and 


270 


THE ENGINEER’S HANDY-BOOK. 

starting, and be a miniature reproduction of it in all other re¬ 
spects; or, in other words, equal piston movements must be rep¬ 
resented by equal movements of the paper throughout the whole 
stroke. To whatever the cord may be attached, whether to a tem¬ 
porary wooden pendulum fastened by a screw to a post, or to the 
beam of a beam-engine, it (the cord) must be at right angles to a 
line between its point of attachment and the pivot of the beam or 
pendulum to which it is attached, when the piston is in the middle 
of its stroke. For instance, suppose the engine to be horizontal, 
and that a wooden pendulum is attached to a light post set up by 
or on the engine, or some other convenient object, or is suspended 
from a joist, the lower end being connected to the cross-head, and 
that the point on the pendulum where the motion is sufficiently 
reduced for the paper drum is higher than the instrument, so that 
the cord must incline downward. In such a case, unless a carry¬ 
ing pulley is used to deflect it to a horizontal direction, or unless 
the point of attachment for the cord is moved as many degrees 
from the centre line of the pendulum as the cord inclines down¬ 
wards, the movement of the pendulum will be too fast at one end 
of its travel, and too slow at the other, and the diagram will be 
distorted. The effects of such distortion will be to cause the ends 
to appear unequal when they are not so, or else to conceal or ex¬ 
aggerate inequalities where they really exist. 

The length of the pendulum may be from one and a half times 
to twice the length of the stroke or more. If too short, the ends 
of the diagram will be distorted, unless the connection between it 
and the cross-head is sufficiently long. The pendulum may be 
attached to some object at the side of the engine, so that it may 
vibrate in a horizontal plane. 

A good substitute for a pendulum consists of a drum about six 
inches in diameter, more or less, on the axis of which is another 
drum, the diameter of which requires to be as much less than the 
other as the movement of the paper is less than the travel of the 
piston. If the drum is mounted in a convenient position, and a 
cord from the large part is attached to the cross-head, and another 


271 


THE ENGINEER^ HANDY- BOOK. 

from the small part to the indicator, a spring in the large drum 
keeps its cord taut, just as the spring in the drum of the in¬ 
dicator keeps its cord taut. 

When two instruments (right and left), are used, it is best to 
fix a sliding-bar alongside of them having the proper motion, 
carrying pins to which the cords are attached, these pins being 
placed between the two instruments so that the cord of each may 
pull towards the other, and the movement of the piston from 
either end of the cylinder may pull the cord of the instrument 
attached to that end, in which case the upper line of each dia¬ 
gram will be drawn while the cord is being pulled. But no per¬ 
ceptible advantage in the way of accuracy need be expected from 
this arrangement, though it is a very convenient one where a large 
number of diagrams are to be taken. 

Analysis of diagrams. —All the various particulars which may 
be learned from the indicator diagram may be classed under three 
heads. 

1. Those relating to the condition of the engine, such as its 
construction, adjustment, etc. 

2. The mean or average pressure exerted on the.piston as an 
element in calculating the indicated horse-power, I. H. P. 

3. The theoretical rate of water consumption. 

Here it is necessary to explain the terms used hereafter to des¬ 
ignate the various parts of the diagram. 

In diagram No. 1 , A A shows the atmospheric line which is 
drawn when both sides of the piston of the indicator are exposed 
to the atmosphere. When tracing such a diagram it is preferable 
to pull the cord by hand, in order to make the atmospheric line 
longer than the diagram ; B C is called the steam line. It is 
formed while steam is entering the cylinder. C is the point of 
cut-off. It cannot always be located exactly by inspection, as the 
closure of the part is generally sufficiently gradual to cause con¬ 
siderable fall of pressure before the port is entirely closed. In 
general, it may be located at the point where the outline of the 
figure ceases to be convex and commences to be concave. CD 


272 


THE ENGINEER’S HANDY-BOOK. 


is the expansion line or curve. D is the point of exhaust, which, 
like that of the cut-off*, may be located at the point of contrary 
flexure , or that point where the expansion line begins to change 
the direction of its curvature. D E is the exhaust line. It com¬ 
mences at the point of exhaust, and may be considered as ter¬ 
minating at the end of the stroke, (though, strictly speaking, it 
does not terminate till the exhaust port closes at F.) E F is 
termed the counter- or back-pressure line, and by some the vac¬ 
uum or exhaust line; but the former terms are more appropri¬ 
ate, as they are applicable to all diagrams, whether from condens¬ 
ing or non-condensing engines. In the diagrams of non-con¬ 
densing engines it is above the atmospheric line, A A ; while 
in condensing engines it is below; but in both cases it rep¬ 
resents some counter-pressure, since a perfect vacuum is unat¬ 
tainable. F is the point of exhaust-closure. Its exact loca¬ 
tion cannot be so readily determined as the points C and D, 
as, although like the former, it is anticipated somewhat by a 
change of pressure, it is not marked by any change in the direc¬ 
tion of the curvature of the line. In perfectly working engines 
it may be located geometrically, but it is seldom necessary to do 
so, since for all practical purposes it is sufficient to know where 
the change of pressure due to the closing of the exhaust begins, 
and its final result. F G is the compression curve, and G B is 
the admission line. These constitute all the lines which belong 
to the diagram proper, and all that are produced by the instru¬ 
ment. 

Fop certain purposes the vacuum line V V, and the clearance 
line If H , diagram No. 1, are drawn, the former parallel to the 
atmospheric line, and at such a distance below it as will repre¬ 
sent, according to the scale used, the pressure of the atmosphere 
as it was, or was supposed to be, at the time and place at which 
the diagram was taken. For this purpose it is usual, when great 
accuracy is desired, to consult a barometer at the time, and 
record its reading on the card; but, in the absence of a barom¬ 
eter, it is usual to assume the pressure at 14*7 lbs. per square 


THE ENGINEER’S HANDY-BOOK. 


273 


inch, which is the average at sea level; but, since the pressure 
diminishes at the rate of T \ lb. for each 189 feet of elevation, 
allowance should be made for the known or estimated eleva¬ 
tion of the locality. It should also be remembered that the 
pressure will vary nearly A lb., and sometimes more, from changes 
in the weather. 

The clearance line HH, diagram No. I, is drawn perpendicular 
to the atmospheric and vacuum lines, and at such a distance from 
the induction end of the diagram, that the space between them 
will bear the same proportion to the whole length of the latter 
as the whole volume of clearance bears to the piston displace¬ 
ment. When the amount of clearance is unknown, and it is not 
practicable either to calculate it or measure it by filling the space 
with water, it must be approximated as near as possible from the 
known clearance of engines of similar construction. The largest 
clearance will be generally found in the smaller sized engines of 
the ordinary single slide-valve type. Five such engines tested at 
the Cincinnati Industrial Exposition of 1875, had the following 
amounts 9, 9^, 10, 114, and 12 per cent, of the cubic contents of 
the cylinder. Next to these will be the larger sizes of the same 
type, in which the clearance will range from 6 to 10 per cent. 
When two slide-valves are used with short, direct ports, but ex¬ 
hausting under the valves, the clearance will average from 3 to 6 
per cent., according to the proportionate length of the stroke, the 
longest strokes having the smallest per cent. Corliss engines, in 
which the stroke is about three times the bore, have about 3 per 
cent. The least amount of clearance is obtained from valves de¬ 
signed to exhaust at both ends of the cylinder, instead of in the 
centre, as in the case of the ordinary single slide-valve. By such 
an arrangement of the steam- and exhaust-valves, the clearance 
has in many instances been reduced to 1| per cent. The clearance 
in poppet-valve engines is more difficult to calculate than in slide- 
valve engines; but, as a general thing, it does not exceed 5 per cent. 
It should be measured with water, when it is desirable to ascertain 
accurately the cubic contents of the clearance. In poppet-valve 

S 


274 


THE ENGINEER’S HANDY-BOOK. 


engines the cut-off and other events are independent and adjust¬ 
able; consequently, diagrams taken from this class of engines are 
free from the limitations attending those taken from slide-valve, 
because advantage is frequently taken of their freedom of adjust¬ 
ment to give an earlier cut-off, or a later depression than is usually 
adopted with slide-valve engines. In all such cases the diagram 
will faithfully state the fact. 

The Most Accurate Methods of Testing the Adjustments. 

The conditions which are mainly instrumental in determining 
the conformation of the diagram are the valves and valve-gear, 
the length and capacity of the steam- and exhaust-pipes and 
ports, the design of the governor-valve, the condition of the 
valves and piston as to leakage, the amount of clearance, the 
speed of the piston, etc. The engineer may be called upon to 
analyze a diagram with reference to all the above conditions, or 
only to accidental derangements. In the first place, he must com¬ 
pare the diagram with one of the best form which can be pro¬ 
duced in practice from the class of engines to which the one in 
question belongs; in the second case, he must discriminate between 
such defects as are due to accidental derangements and those that 
are due to design and construction, which cannot be remedied 
without the substitution of new parts. Suppose the engine to be 
of the throttling kind, of the best attainable construction and 
adjustment, its diagram should possess the following general 
features: 

1. The initial pressure at B, diagram No. 1, should be as high 
at least as any subsequent pressure; and if the engine is not 
driving its maximum load, and the steam is in consequence more 
or less throttled, the pressure should begin to fall at B, and con¬ 
tinue to do so at a tolerably uniform rate, until the point of cut¬ 
off, C, is reached. 

2. The cut-off, when obtained by means of lap in the slide- 
valve, cannot, as a general rule, take place with advantage earlier 


/ 


THE ENGINEER'S HANDY-BOOK. 



Richards’ Parallel Motion Indicator. 


275 


































































































































































































































































276 


THE ENGINEER’S HANDY-BOOK. 

in the stroke than about f, as the angular advance necessary to 
give any earlier cut-off would involve atoo early exhaust and com¬ 
pression. 

3. From the cut-off, C, to the release, D, is the expansion 
curve. Assuming the applicability of the Mariotte law to expand¬ 
ing steam, the shape of the expansion curve, C E , should be such 
that, if the distance from any point in it to the clearance line, H 
H, taken on a line parallel with the atmospheric line, be multiplied 
by the distance from the same point to the vacuum line measured 
vertically, the product will be the same for all points in the curve. 
Hence, if at the commencement of the curve, the two measure¬ 
ments are multiplied together, and the product divided by the 
distance from the clearance line to any other point, the quotient 
will be the distance of that point from the vacuum line, or the 
pressure at that point, if the pressure scale is used for the measure¬ 
ments. ' 

4. The release at D will take place earlier or later, according to 
the amount of lap, both steam and exhaust, that is introduced. 
The steam-lap affects it indirectly, as, the greater it is, the greater 
the angular advance necessary to maintain the proper lead. Lap 
on the exhaust side affects it directly without change in the angu¬ 
lar advance, by opening the port so much later, and consequently 
closing it so much earlier. The requirements of perfect working 
are, that it shall be early enough to release the piston of all undue 
back pressure before much of the return stroke is made, and late 
enough not to materially diminish the power of the engine. The 
conformation of diagram No. 1, page 291, shows about as early 
an exhaust as is admissible, because little or nothing would be 
gained by a later one, as the steam is not thoroughly exhausted 
until the piston has moved a short distance on its return stroke; 
and, while a later release would add a little to the average forward 
pressure, it would also increase the back pressure. Besides, a later 
release would involve either a later cut-off or an earlier compres¬ 
sion ; and, although the general practice is to place all these events 
later than is shown on the diagram, such practice is not calculated 


THE ENGINEER’S HANDY-BOOK. 277 

to realize the best possible steam economy with that class of en¬ 
gines. 

5. The back-pressure line, EF, should coincide with the atmos¬ 
phere, or nearly so, in non-condensing engines and with the 
pressure shown by the vacuum-gauge in condensing engines. 
When it is in excess in either case, it indicates insufficient capac¬ 
ity in the exhaust-ports or pipes, or both. 

6. The compression curve, F G, owes its form to the same laws 
that govern the expansion curve, and its degree of conformity to 
theory may be tested by the same methods. The only differences 
between the two are in the quantities of steam evolved in their 
production, and the order of their formation ; the ending of one 
corresponding to the beginning of the other. As to the amount 
required to satisfy the best conditions, some difference of opinion 
exists. It is ascertained that a certain amount is advantageous, 
as a means of arresting the momentum of the reciprocating parts, 
while changing the direction of the force on the crank-pin in a 
more gentle and quiet manner, than would be done by the admis¬ 
sion of steam as an opposing force. If the compression, or, more 
properly speaking, the cushion has fulfilled its functions, the in¬ 
duction will find the parts already prepared for the shock, and 
prevent a jar or thump. The maximum pressure reached by the 
cushion should never be greater than the average initial pressure; 
but within this limit considerable latitude exists, as, while it dimin¬ 
ishes the power of the engine, it lessens the consumption of steam. 
The less the exhaust-lap, the earlier the exhaust will take place, 
and the later the compression, and vice versa. 

7. The lead line, G B , need not conform to any arbitrary 
standard. It satisfies the eye of the engineer best when it is ver¬ 
tical, or nearly so; but it may lean slightly inwards, indicating 
deficiency of lead, or outwards, indicating excess, without affecting 
the economy of the engine, and in most cases without sensibly 
affecting the smoothness of its running. In many cases the com¬ 
mencement of the lead line proper cannot be exactly located; but 
engines always run best when the compression and lead lines join 

24 


278 the engineer’s handy-book. 

each other with an easy curve. When a single slide-valve is used, 
both the steam- and exhaust-lap must be provided for in its con¬ 
struction, and cannot be subsequently changed without a change 
of proportion. But since it is not the absolute amount of lap, but 
its amount relatively to the travel of the valve, which determines 
its influence, it follows that, by reducing the travel, the lap both 
steam and exhaust will be virtually increased, and vice versa. 
Any change of travel must be accompanied by such change of 
angular advance as will maintain the proper lead. The adjust¬ 
ment of the cut-off by the link-motion of the locomotive is an 
instance of such change of travel and angular advance. 

In the foregoing description all the capital letters refer to dia¬ 
gram No. 1, on page 291. 

When two slide-valves are used, each performing the functions 
of induction and exhaust at its own end of the cylinder, the steam- 
lap may be increased by setting them farther apart, and dimin¬ 
ished by contracting their connection ; but in such cases steam-lap 
is obtained at the expense of the exhaust-lap, and vice versa. 
Having learned from an engine embodying correct construction 
and performance the general features which should characterize 
a diagram, the engineer will have no difficulty in recognizing 
defects as well as deviations from diagram No. 1, on page 291. 
These conditions should be understood before the slide-valve, 
throttling engine diagram can be intelligently criticised. 

Diagrams taken from Automatic Cut-Off Engines. 

The points of difference between diagrams from automatic 
cut-off engines and those from slide-valve engines will be mainly 
found in the steam lines, the points of cut-off, and the expansion 
curve. When the automatic cut-off engine is worked in accord¬ 
ance with the theory of its operation, the steam is never throttled 
for the purpose of regulating the speed, but is admitted freely to 
the valves, the speed being regulated solely by means of variations 
in the point of cut-off. Hence, the steam line should indicate a 


279 


THE ENGINEER’S HANDY-BOOK. 

pressure equal to that in the boiler, whatever the load may be, 
and would undoubtedly do so, if the proportions were good and 
the valve-gear in perfect order. The necessary difference, then, 
between the throttling and automatic cut-off engine diagrams, 
may be thus stated. In the former, the height of the steam line 
varies with the load, the length remaining the same; in the 
latter, the length of the steam line varies with the load and 
pressure, the height remaining always approximately that of the 
boiler pressure. 

The theoretical diagram. — From what has been said in the 
foregoing paragraphs, it is clear that a theoretical diagram may 
be constructed, representing perfect performance on the automatic 
cut-off principle, which cannot be done in the other case, as the 
height and conformation of the steam line depends on conditions 
too numerous and complex for analysis. Thus, with a given 
boiler-pressure for a steam line, a straight horizontal line may be 
drawn, corresponding with that pressure, and, from a given point 
of cut-off, an expansion curve may be drawn having the properties 
already described, and reaching to the end of the stroke. If the 
remaining terminal pressure is greater or less than the counter¬ 
pressure, a vertical line extending upwards or downwards to the 
height required by the counter-pressure will represent a perfect 
exhaust line. Then, for the return stroke, a line coincident with 
the atmosphere or a perfect vacuum, according as the engine is 
non-condensing or condensing, will represent the counter-pressure, 
and a vertical line up to the beginning of the steam line will 
represent the admission line and complete the figure. 

If a compression curve is desired, it may be drawn through the 
assumed or actual point of exhaust-closure on the counter-pressure 
line, but such a curve cannot originate from a perfect vacuum. 
Hence, when the diagram is from a condensing engine, and the 
actual compression curve is to be tested by a theoretical one, the 
latter must be based on the actual counter-pressure present at the 
closure of the port. 

This theoretical diagram being for the present assumed to be 


280 T HE engineer’s handy-book. 

perfect, not in the sense of representing the best conditions in an 
economical point of view, but only the most perfect performance 
possible under given conditions, is nevertheless the standard with 
which the actual one is to be compared, and by which it is to be 
judged. For this purpose it is customary to draw it around the 
actual, so that the imperfections of the latter may be readily seen 
and their magnitude estimated. 

Application of the Theoretic Curve. 

On tracing the theoretic curve on diagrams from different 

engines, a great difference in the degree of theoretical correctness 
shown in their expansion curves is revealed. The deviation from 
the theoretical is always in the direction of a higher terminal 
pressure, unless it is caused by excessive piston leakage. This 
may be explained on two suppositions, viz., leakage of the cut¬ 
off valves, and evaporation of the spray or water of supersat¬ 
uration in the steam during expansion as the pressure decreases. 
Till recently the former was the only explanation offered, but, in 
more modern times, the latter has almost entirely displaced it. 
There is no doubt that both causes are in some degree responsible 
for the phenomenon, but the diagram itself seldom furnishes any 
reliable indications pointing to either cause to the exclusion of the 
other; nor does a study of the conditions under which the greatest 
incorrectness shows itself throw much light on the subject. As a 
general rule, large engines give more correct expansion curves than 
small ones, though numerous exceptions are met with in both 
cases. 

Incorrectness is generally less with heavy loads than with light 

ones. But both the foregoing facts can be explained on either 
theory, since, with equal care in the fitting of the valves, a large 
engine will leak less in proportion to the amount of steam used 
than a small one. But the evaporation of the spray will be less 
perfect in the former than in the latter, owing to the longer time 
occupied in effecting a given degree of expansion, during which 


THE ENGINEER’S HANDY-BOOK. 281 

the heat of the water, instead of being effective for evaporation, 
will be dissipated. In small, fast-running engines the steam under¬ 
goes a more rapid expansion, and the heat, rendered sensible by 
the removal of the pressure, has less time to be taken up by the 
cylinder walls, and is consequently more effective in vaporizing 
the moisture. Another fault in small engines is imperfection in 
the cut-off valves. Both causes afford better facilities to operate 
with an early than with a late cut-off, the longer time afforded by 
the former, and the less pressure under the valve, being favorable 
to the greatest leakage ; and the greater the change of pressure is, 
the more favorable it will be to the evaporation of the moisture. 

If, however, the deviation should (other things being equal) be 
found to be greatest when the water is high in the boilers, or when 
the steam is being rapidly generated, that fact would point to the 
spray theory as the undoubted cause of part of it. Such appears 
to be the case to some extent, though the observations taken on 
that point have not been numerous and careful enough to be of 
much value. But, whatever may be the cause of the phenom¬ 
enon, it is so general that, whenever a very correct curve is met 
. with, the suspicion of piston or other leakage, the tendency of 
which is to lower the pressure during expansion is always justly 
raised, and should be disposed of by test or otherwise, before such 
a curve can be confidently accepted as evidence of correct per¬ 
formance. Nevertheless, very correct curves are sometimes met 
with when piston leakage does not exist. 

The most obvious lesson to be deduced from the facts at present 
in our possession, seems to be that, when any considerable in¬ 
correctness is met with in the curves of the diagrams taken from 
large engines, a considerable amount of leakage may be confi¬ 
dently inferred. But, in the case of small engines, particularly 
fast-running ones, the amount of incorrectness which may be 
caused by re-evaporation is undoubtedly greater than in large 
ones; but even in them the cut-off valves should not be too read¬ 
ily excused without examination. 

24 * 


282 


THE ENGINEER’S HANDY-BOOK. 


The Initial Pressure, or Steam-Line. 

A close approximation of the steam-line of an automatic cut¬ 
off diagram to the boiler pressure is rightly regarded as an indi¬ 
cation of good construction and performance. Other things being 
equal, that engine which most nearly obtains the highest boiler 
pressure on its piston at the commencement of the stroke, may 
cut off the earliest — attain the highest ratio of expansion — and 
exhaust the steam at the lowest pressure. The last condition is the 
test of all improvements designed to promote steam economy, as, if 
they do not produce a lower terminal pressure for the same work, 
they do not fulfil the conditions for which they were intended. It 
is not sufficient to rely on the steam-gauge as a test of the steam¬ 
line, unless it has been recently tested and found correct. Most 
steam-gauges deteriorate by use, especially if exposed to undue 
heat or cold. When practicable, the engine should be stopped 
and blocked, or placed on the centre, steam admitted to the indi¬ 
cator at full pressure, and a line traced by hand. If this has been 
done, and a difference of four or five pounds between boiler and 
initial pressure be detected, how is the difference to be accounted 
for? The pipe may be too small, long, or crooked, or the ports 
be inadequate; or both these defects may exist. To test this 
matter, a connection should be made between the indicator and 
the steam-pipe above or below the throttle, as may be thought 
preferable. By means of this connection, a diagram representing 
the fluctuations of pressure in the pipe is produced over the engine 
diagram. A diagram produced in this way will show whether 
the loss of pressure is due to the ports or the pipe. In such a 
case, the pressure falls, when it is admitted to the cylinder, until it 
exceeds the initial pressure but little more than one pound. Then, 
as soon after the steam is cut off, as the space immediately above 
the cut-off' valve can fill, the pressure rises, and the momentum 
of the steam in the pipe evidently carries it above that of the 
boiler, and about the middle of the stroke it falls again, evidently 
going below the boiler pressure. At about three-fourths of the 


283 


THE ENGINEER’S II ANDY-BOOK. 

stroke it rises again, but this time not so high as it did at its first 
rise, probably not above boiler pressure. These secondary fluctu¬ 
ations possess no special significance, except as showing that the 
boiler pressure is to be determined by finding the mean of their 
extremes. Their frequency during the stroke will depend on the 
length of the pipe as determining their frequency in time, and on 
the speed of the engine as determining their relative frequency." 
The pressure of the steam also affects them, as high-pressure steam 
is denser than low. The trouble involved in making the necessary 
connection for such a diagram will of course exclude them in most 
cases, but their value to the engineer, as a means of arriving at 
correct proportions for the pipes and ports, will be apparent. 


The Mean Effective Pressure. 

Whatever uncertainty may attach to the inferences deduced 
from indicator diagrams, there is every reason to believe that, 
provided that the spring is correct, the instrument in good work¬ 
ing order, and its indications mathematically calculated, the con¬ 
clusions will be reliable. The usual method of calculating the 
mean effective pressure is to divide the diagram into any suitable 
number of equal spaces by lines or ordinates , to measure the centre 
of each space with the proper scale, and to take the average of-the 
several pressures by dividing their sum by their number. But 
since it is easier to measure on a line than to guess at the centre 
between two lines, it will be preferable to make the first and last 
spaces half the width of the rest, which will make the lines stand 
in the centres of equal spaces. The measurements are then taken 
on them. Diagram No. 1, page 291, is lined in this manner. 
The most expeditious and accurate method of obtaining the 
average of these ordinates is to take a slip of paper, apply its 
edge to each of them in succession, and mark their combined 
length on it. This length in inches multiplied by the scale of the 
spring used, and the product divided by the number of ordinates 
measured, will give the desired average. By using a sharp-pointed 


284 


THE ENGINEER’S HANDY-BOOK. 


instrument, as the point of a knife, thrusting it into the paper at 
tiie foot of each ordinate, moving it to the top of the next, and 
carrying the strip with it, the measurement may be taken with 
great ease and rapidity. 

The simplest method is to measure the ordinates between the 
direct and counter-pressure lines. This will give results accurate 
enough for most purposes; in fact, it will give the mean average 
of the two ends with entire accuracy, and this must always be ob¬ 
tained as a basis for calculating the power of the engine. But, 
since a diagram, from either end of the cylinder, represents, by its 
upper line, the pressure which impels the piston during one stroke, 
and by its lower, the counter-pressure which opposes it during the 
stroke in the opposite direction, it follows that, from either diagram 
alone, a corrrect balance for either of the two strokes which it 
represents cannot be struck. To do this, the mean counter-pressure 
of the one must be deducted from the mean impelling pressure of the 
other. To obtain these pressures separately, it is necessary to draw 
and measure the ordinates from the lines representing them to the 
vacuum line. This, however, is unnecessary, except for very ac¬ 
curate analysis. In general, the counter-pressure of the two strokes 
will be very nearly equal, especially if the exhaust and cushion 
are properly equalized ; and even where they are unequal, the final 
average of the two ends will be correct. 

The number of ordinates may preferably be one-fourth, one- 
third, one-half, or equal to the number representing the scale used ; 
in which case it will only be necessary to multiply the combined 
length of the ordinates (or the string, as it may be called) by 4, 
3, or 2, as the case may be, to obtain the desired result. If the 
number is equal to the scale, the multiplier, being 1, need not be 
used. Thus, suppose the scale to be 40, the number of ordinates 
20, and the string 14^ inches. As the scale represents twice the 
number of ordinates, the string being multiplied by 2 will give a 
product of 29 lbs. mean pressure. Or suppose diagrams to be 
taken from both ends of the cylinder, either on the same paper or 
separately, and the one to be calculated and averaged with the 


THE ENGINEER’S HANDY-BOOK. 2S5 

other. The string of both may be taken together on the same 
strip, and if the scale is twice the number of ordinates, the length 
of the string will give the mean pressure at once without multi¬ 
plying. When taking such a continuous string for two diagrams, 
the termination of the first should be marked with a pencil, so 
that the two may be compared. 

When diagrams are met with, in which the expansion curve 
crosses the counter-pressure line, the string should be taken from 
the beginning up to the point where the lines cross, and after that 
in a reverse direction on the strip, so as to cancel the part of the 
string already made. When the terminal end is reached, what 
remains of the string first made will give the mean effective press¬ 
ure (M E. P.) in the usual way; or the total mean impelling and 
counter-pressure above vacuum may be found separately, and their 
difference ascertained. 

To Space the Ordinates. 

Draw vertical lines touching the ends of diagram No. 1, A B 
K I } and apply a rule across them in a more or less oblique direc¬ 
tion, till some division on the rule, as y’g-, ybj, tV> or d will divide 
the distance between the points where the rule crosses the lines, 
the desired number of two or three times the number of times. 
Thus the line H Cl , in diagram No. 1, is 3f inches long, and 
contains the j’g division 60 times; consequently, r s % pointed off at 
each end, and T 3 e for the other spaces, will correctly divide the 
diagram for 20 ordinates. With a little greater obliquity the dis¬ 
tance would be 4 inches, when y 1 ^ inches would be right for the 
end spaces, and for the rest. 

% 

To Calculate the Indicated Horse-Power (I. H. P.). 

Multiply the speed of the piston in feet per minute by the area 
of the piston in square inches, and divide the product by 33,000. 
The result will be the H. P. for each pound of M. E. P., or the 


286 the engineer’s handy-book. 

H. P. value of each pound. See table on page 290. Then multiply 
the M. E. P. by this value. This method is preferable to multi¬ 
plying by the M. E. P. before dividing, as, when several diagrams 
from the same engine representing varying loads are to be calcu¬ 
lated, the value when once obtained will answer for all, the speed 
being practically the same in each case. The area of the piston- 
rod is generally ignored in such calculations, though it will dimin¬ 
ish the area of one side of the piston about 

Theoretical Economy. 

If the steam used by an engine was known to be saturated, and 
at the same time free from any excess of water, and if it both 
entered and left the engine in that condition, it would be easy to 
calculate from the diagram the amount of water which the engine 
would use in a given time, supposing it to be practically free from 
leakage. Under such conditions the expansion and compression 
curves would conform rigidly to exact theory, and the total piston 
displacement for one stroke, divided by the volume of terminal 
pressure, and the displacement up to any point in the curve di¬ 
vided by the volume of the pressure at that point, would give the 
same result wherever the point was taken, which result would be 
the number of cubic inches of water used during that stroke. 
Unfortunately, the nature of steam is such that no exact calcula¬ 
tions of water consumption can be made. Even if its exact con¬ 
dition as it enters the engine is known, as it may be by the calor¬ 
imeter test, its capacity for receiving and parting with heat is so 
great that its condition changes immediately upon entering the 
cylinder, so that, after deducting the water of supersaturation, 
known to be present before it enters the. cylinder, the diagram 
will still fail to account for all of the remainder. Nevertheless 
such calculations are frequently made, and as a means of ascer¬ 
taining the relative economy of different engines, and of different 
loads, pressures, and adjustments in the same engine, they possess 
great value, since, whatever uncertainty may exist as to the unin- 


THE ENGINEER’S IIANDY-BOOK. 


287 


dicated consumption, it may, so far as the engine is concerned, 
be assumed to be the same in each of the cases under compar¬ 
ison. 

When it is desired to approximate as nearly as possible to the 
actual consumption by calculation, a certain amount must be 
added to the theoretical result. This amount varies from 10 to 50 
per cent., according as the conditions are more or less favorable; 
but when they are so unfavorable as to require an addition of 50 
per cent., they are obviously so bad as to call for repairs and 
changes, rather than elaborate calculations. When the conditions 
are generally good, a careful examination of them will make it 
possible to fix the margin of uncertainty within tolerably narrow 
limits. A large engine, with well-jacketed cylinder and tight-fitting 
valves and piston, will generally require at least 10 per cent, ad¬ 
dition, independent of the percentage of unevaporated spray, 
which may exist in the steam with which it is supplied, and this, 
unless the boiler is so set as to superheat the steam, will require 
from 10 to 25 per cent. more. In fact, the margin of uncertainty 
due to the boiler is much greater than that due to the engine, as 
not only will differently constructed boilers vary greatly in the 
amount of unevaporated water given off* but great difference will 
be found to exist with the same boiler, according to the height the 
water is carried, the rapidity with which it is evaporated, the 
amount of impurities present in the feed-water, or which have 
accumulated in the boiler, and many other conditions. Thus a 
rapidly fired generator, containing a large area of heating surface 
in proportion to the amount of water and little steam room and 
superheating surface, may, and often will, give off* nearly or quite 
as much unevaporated water as is contained in the steam. The 
only fair way to test the performance of an engine is to test the 
steam as it enters it, both as to moisture and heat. It should 
also be borne in mind that, according to Trowbridge’s tables, the 
difference between the economy of engines of over ten cubic feet 
capacity of cylinder and those under one cubic foot, is about 12 
per cent, in favor of the larger size. 


288 


THE ENGINEER’S HANDY-BOOK. 


\ 


How to Calculate Theoretical Rate of Water Consump¬ 
tion. 

The total displacement per stroke in cubic inches divided by 
the volume of the steam at release pressure, and the quotient 
multiplied by the number of strokes per hour, will give the total 
cubic inches used per hour. This, divided by 27'648, the number 
of cubic inches of water per pound, will give the total number 
of pounds used per hour, which, if divided by the I. H. P., will 
give the result in pounds per I. H. P. per hour. This is the usual 
method; but, when the rate only is desired, a shorter process may 
be adopted, based on the fact that, from a given diagram, the re¬ 
sult would be the same, whether the calculations are based on the 
actual size of the engine, or some other size is assumed, say a 
smaller size; as, although the total consumption would be changed, 
the divisor would also be proportionately changed. 

Suppose the engine to be of such displacement as to develop 
one horse-power with one pound pressure, and that it is driven by 
that pressure of water instead of steam. It being but one horse¬ 
power, its total consumption per hour and per horse-power j)er 
hour will be the same. Being driven by water, its displacement 
will be its water consumption, which will be obtained as follows: 
A horse-power is 33,000 lbs. lifted one foot high per minute, or 
33,000 x 60—1,980,000 lbs. per hour, or 1,980,000 x 12=22,760,000 
lbs. lifted one inch per hour, which would be the displacement of 
such an engine in cubic inches, and consequently its consumption 
in cubic inches of water when driven by water. Then, taking 
27*648 cubic inches of water per lb., we have 22,760,000 h- 27*648 
= 859,375 as its rate of consumption m lbs. of water per H. P. 
per hour. Then, if the pressure were greater than one lb., the 
amount used would be as many times less than the above, as the 
pressure was greater than one lb.; and also, if it were driven by 
steam instead of by water, the amount used would be as much 
less, as the volume of steam at the terminal pressure was greater 
than an equal weight of water. It follows that if we divide 


THE ENGINEER’S HANDY-BOOK. 


289 


,859,375 by the product of the mean effective pressure, and the 
volume of the total terminal pressure of the diagram under analy¬ 
sis, the quotient will be the desired rate, whatever the size and 
speed of the engine. The use of this constant number renders 
the operation more easy and short, and, except in the case of the 
compound engine, entirely independent of all data except those fur¬ 
nished by the diagram itself, the scale of indicator being known. 

The terminal pressure for this and subsequent rules is found, 
when the exhaust takes place before the end of the stroke is 
reached, by continuing the expansion curve to the end of the 
stroke. In other words, it is not what the pressure may be at the 
moment of release, but what it would have been if it had not 
been released until the end of the stroke. 

How to apply the rule to diagrams taken from compound en¬ 
gines when the strokes of the two cylinders are equal. Multiply 
the M. E. P. of the low-pressure cylinder diagram by the area of 
its piston, and divide the product by the area of the piston of the 
high-pressure cylinder. The quotient will be the pressure, which, 
acting on the low-pressure piston, will be equivalent in energy to 
that acting on the high-pressure piston. Then add this quotient 
to the M. E. P. of the high-pressure cylinder, and with its mean 
pressure so augmented treat it in all respects as an ordinary dia¬ 
gram. Or the process may be reversed, i. e., the diagram from 
the low-pressure cylinder, with its M. E. P. augmented by the 
quotient of the product of the area and M. E. P. of the horse¬ 
power cylinder divided by the area of the low-pressure cylinder, 
may be treated as an ordinary diagram; but the result by this 
method will be less than by the first. 

When the two cylinders have different strokes as well as dif¬ 
ferent piston areas, multiply together the M. E. P. piston area, 
and stroke of the high-pressure cylinder, and divide the product 
by the product of the piston area of the low-pressure cylinder 
multiplied by its stroke. The quotient will be the amount to aug¬ 
ment the M. E. P. of the horse-power cylinder before treating it 

as a simple diagram. 

25 


T * 


290 


THE ENGINEER’S HANDY-BOOK. 

The same calculations may be more conveniently made by 
means of the following table; to use it, proceed according to the 
following rule: 

Find under P the number which corresponds nearest to the 
terminal pressure of the diagram, and multiply the terminal 
pressure by the number opposite it to the right under W, and di¬ 
vide the product by the M. E. P.; the quotient will be the rate of 
water consumption in lbs. per 1 horse-power per hour. 


p. 

w. 

p. 

w. 

p. 

w. 

p. 

W. 

P. 

w. 

k 5 

37*95 

27 

34*37 

49 

33*18 

71 

32*46 

93 

31*96 

0 

37*54 

28 

34*29 

50 

33*14 

72 

32*43 

94 

31*94 

7 

37*22 

29 

34*22 

51 

33*10 

73 

32*40 

95 

31*92 

8 

36*93 

30 

34*15 

52 

33*06 

74 

32*38 

96 

31*90 

9 

36*67 

31 

34*08 

53 

33*02 

75 

32*36 

97 

31*88 

10 

36*44 

32 

34*01 

54 

32*98 

76 

32*34 

98 

31*86 

11 

36*24 

33 

33*95 

55 

32*94 

77 

32*32 

99 

31*84 

12 

36*06 

34 

33*89 

56 

32*91 

78 

32*30 

100 

31*82 

13 

35*89 

35 

33*83 

57 

32*88 

79 

32*28 

101 

31*80 

14 

35*73 

36 

33*77 

58 

32*85 

80 

32*26 

102 

31*78 

15 

35*59 

37 

33*72 

59 

32*82 

81 

32*23 

103 

31*77 

16 

35*46 

38 

33*67 

60 

32*79 

82 

32*20 

104 

31*75 

17 

35*34 

39 

33*62 

61 

32*76 

83 

32*18 

105 

31*73 

18 

35*22 

40 

33*57 

62 

32*73 

84 

32*16 

106 

31*71 

19 

35*10 

41 

33*52 

63 

32*70 

85 

32*14 

107 

31*69 

20 

34*99 

42 

33*47 

64 

32*67 

86 

32*12 

108 

31*67 

21 

34*89 

43 

33*42 

65 

32*64 

87 

32*09 

109 

31*65 

22 

34*79 

44 

33*38 

66 

32*61 

88 

32*07 

110 

31 *63 

23 

34*70 

45 

33*34 

67 

32*58 

89 

32*05 

111 

31*61 

24 

34*61 

46 

33*30 

68 

32*55 

90 

32*03 

112 

31*59 

25 

34*53 

47 

33*26 

69 

32*52 

91 

32*00 

113 

31 *57 

26 

34*45 

48 

33*22 

70 

32*49 

92 

31*98 

114 

31*55 


Example from same diagram. The terminal pressure is 25*5 lbs., 
aud the mean of the numbers under W, opposite to 25 and 26 
(34*50 and 34*41), is 34*45. The mean effective pressure being 
30*5, the operation is as follows : 25*5 x 34;45 -r- 30*5 — 28*8 lbs. 
per horse-power per hour. 

As a matter of course, the theoretical rule of water consump¬ 
tion, as deduced from indicator diagrams, can never be fully 
realized in practice. It can only be approximated. 





































THE ENGINEER’S IIANDY-BOOK. 


291 


Indicator Diagrams. 


All indicator diagrams are the perfect pictures of the perform¬ 
ances of the engines from which they are taken, provided the in¬ 
dicator is in good order. There are two senses in which a diagram 
is said to be perfect or imperfect. First, it may he in perfect con¬ 
formity to existing conditions, as clearance, load, steam-pressure, 
etc., though all of these conditions may be far from the best; or, 
second, it may not only conform to the above conditions, but it 
may represent the best attainable conditions, which would include 
no clearance at all, which is unattainable. 



Explanatory Diagram No. 1. 


In diagram No. I, B C shows the steam line; C, point of cut-off; 
CD, expansion curve; D, exhaust; D E, exhaust line; EF, counter¬ 
pressure line; F, point of exhaust-closure; F G , compression curve; 
G B , admission line ; A A, atmospheric line ; V V, vacuum line ; 
If H, line representing the clearance; 0 00, ordinates for ascertain¬ 
ing the average pressure; I, continuation of the expansion curve to 
end of stroke, to give the terminal-pressure for the purpose of calcu¬ 
lating theoretical consumption; J, the point in the compression curve 
where the pressure equals the terminal; consequently, IJ is the pro¬ 
portion of the whole stroke taken as the measure of the consumption. 






292 


THE ENGINEER’S HANDY-BOOK. 




Diagram No. 2 was taken from a Buckeye automatic cut-off 
engine 22 x 44; piston speed, 520 feet per minute; scale, 40; 


clearance, 1*75 per cent.; mean effective pressure, 36 lbs. It shows 
very perfect performance both of the engine and indicator. 

Diagram No. 3 was taken from a locomotive built at the Baldwin 


Locomotive Works, for the Pennsylvania Railroad Company, to 
run on the Philadelphia and Erie Railroad. Diameter of cylinder, 







THE ENGINEER’S HANDY-BOOK. 293 

18 inches; stroke, 22 inches; speed, 93 revolutions per minute; 
boiler-pressure, 115 lbs. per square inch; initial-pressure, 100 lbs.; 
mean effective pressure, 80 60 lbs.; clearance, 4 per cent. At the 
time the diagram was taken, the engine was pushing a train of 15 
loaded cars, whose gross weight was 302 tons, throttle-valve wide 
open, against a grade of 74 feet rise per mile. Adhesion per ton 
of load 600, resistance per ton due to grade 35*7 lbs. The slight 
rounding of the induction corner was probably caused by too 
much pressure on the pencil, which prevented it from rising till 
after the paper started to move. The diagram is very good, The 
expansion curve, as far as can be observed from its limited extent, 
is correct, and its compression curve very nearly so. 

Diagram No. 4 was taken from a Wardwell valveless engine 
on exhibition at the Centennial Exposition held at Philadel- 



Diagram No. 4. 

phia. The conditions under which the diagram was taken are 
not specified, but it will be observed that the exhaust-port opens 
quite late and quick, which explains the fact that the curve is all 
on the lower corner. The cut-off is quick and sharp. The induc¬ 
tion and compression lines are also good. The lateness of the ex¬ 
haust is a necessary result of the movement which produces it, as 
it is effected by a partial rotation of the piston-head, derived from 
25* 




294 


THE ENGINEER’S HANDY-BOOK. 



the lateral vibration of the connecting-rod, which gives a movement 
exactly equivalent to that of an eccentric without angular advance. 
Diagrams No. 5 were taken from an old Corliss engine that 

had been running in 
the penitentiary at 
Jackson, Michigan, 
for about 25 years. 
Scale, 40; clearance 
about 8 per cent.; 
mean effective press¬ 
ure, 47*5 lbs.; mean 
of the two ends, 47 J- 
lbs. It possesses no 
special interest, save 
to show the effects of 
adjustment due to 
long wear and use, 
without the applica¬ 
tion of an indicator or 
any other test. The 
excessively late in¬ 
duction would cause 
a perceptible loss of 
useful effect in the 
steam. The exhaust 
is much less perfect 
from one end than 
from the other, and 
much of the benefit 
of the vacuum is 
thereby lost. The 
pencil was held on 
Diagrams No. 5. during several revo¬ 

lutions, and, the governor being over-sensitive and fluctuating, 
different lines were drawn at each revolution. 




THE ENGINEER’S HANDY-BOOK. 


295 



Diagram No. 6 was taken from a Harris Corliss engine oper¬ 
ating at the Cincinnati Industrial Exposition of 1875. Size, 16 
X 48; speed, 60 revolu¬ 
tions, or 480 feet of piston 
speed per minute. Both 
the isothermal, I, and the 
adiabetic curves are drawn. 

In tracing the latter, the 
following process was used. 

The horizontal lines, A,B, 

C, D , E, F, G, represent to¬ 
tal pressures (above vacu¬ 
um) of, respectively, 90,80, 

70, 60, 50, 40, and 30 lbs., 
the volumes of which are 
298, 333, 378, 437, 518, 

640, and 838. At the point, 

H y where the curve termi¬ 
nates, the total pressure is 
191bs.,thevolumeof which 
is 1290. Now, it is evident 
that if the distance, II «/, 
which is 47 inches, repre¬ 
sents 1290, the distance, 

G J, representing 838, 

(the volume of 30 lbs.,) 
will be proportionately as 
much shorter than H J 
as 838 is less than 1290. 

Hence, the formula, 1290 : 

47 : : 838 : 3 05, or 

47 x 838 QAr 
~ -[ 29 q " ~ 3*05, will give 

this distance (3*05) from 

the clearance line, J , to Diagram No. 0. 


: I ^ 






296 


THE ENGINEER’S HANDY-BOOK. 


that point in the curve which shows a pressure of 30 lbs. In like 

4-7 x 640 

manner the formula for the point, F, will be — ~ —— for F, 

4*7 x 518 1^00 

—-p-——, and so on for the other lines, D, C, B, A. The fore- 
1290 


going process may, however, be shortened. 



Diagram No. 7. 


Diagram No. 7 

was taken from a 
Holly engine lo¬ 
cated at the water¬ 
works of Rochester, 
N. Y. Size, 16 x 
26 - 9 inches; speed 
not given, but it va¬ 
ries greatly, as it is 
regulated by the wa¬ 
ter-pressure ; mean 
effective pressure, 
30 lbs.; scale, 32 lbs. 
The cut-off valves 
of these engines con¬ 
sist of a single-pop¬ 
pet valve placed on 
the cover of the 
steam - chest, which 
cuts off' the steam 
for both strokes; 
hence, all the steam 
in the chest is sub¬ 
ject to expansion 
along with that in 
the cylinder, which 
has the effect of enor¬ 
mous clearance on 
the diagram. The 
theoretical curve 






THE ENGINEER’S HANDY-BOOK. 


297 



shown is not based on the actual clearance subject to expansion, 
but on a reasonably small amount, not greater than the average 
of true automatics 
of good construction ; 
consequently, it is not 
a test of the conform¬ 
ity of the curve to the 
actual conditions, but 
rather a means of 
comparing the eco¬ 
nomical results of 
such an arrangement 
with engines of the 
best automatic type. 

Diagram No. 8 was 
taken from a Wlie'el- 
ock automatic cut-off 
engine on exhibition 
at the Centennial Ex¬ 
position. Size, 18 X 
48; clearance, 4^ per 
cent.; scale, 30; mean 
effective pressure, 12 
lbs.; piston speed, 50 
revolutions, or 400 
feet per minute. A is 
the adiabatic and I the 
isothermal curve,both 
being based on actual 
terminal - pressure. 

The diagram is quite 
good for a light load, 
though the very si ight 
compression is not in 
accordance with the weight of opinion as to what constitutes sound 

practice. 








298 


THE ENGINEER^ HANDY-BOOK. 


Diagrams No. 9 were taken from a Cummer slide-valve engine. 



with riding cut-off, built at De¬ 
troit, Michigan. Size, 26 x 36 
inches ; speed, 80 revolutions, or 
480 feet per minute; scale, 30; 
mean effective pressure not giv¬ 
en ; clearance is unknown, but as¬ 
suming it to be 4 per cent., which 
is about what its construction re¬ 
quires, the theoretical curve at 
one end shows correct perform¬ 
ance, but that at the other shows 
considerable deviation. In such 
a case, taking the size of the en¬ 
gine into consideration, the ex¬ 
planation of this defect lies be¬ 
tween two suppositions, 1st, that 
the cut-off valve leaked at one 
end and not at the other; or, 2d, 
that the volume of clearance is 
greater at one end than at the 
other. If the engine had been 
a small one, the supposition of 
the escape of the expanding steam 
from the right-hand end through 
a leaky slide-valve would be ad¬ 
missible ; but the curve at that 
end is just what an engine of the 
size given should produce with¬ 
out leakage of any kind; hence, 
the left hand is the one to which 
attention is directed for the cause 
of the difference between the two, 
and the supposition of a leaky 
cut-off valve is the more prob¬ 
able one. 


Diagrams No. 0. 






THE ENGINEER’S HANDY-BOOK. 299 

Diagram No. 10 was taken from one of a pair of 16 x 30 inch 
single slide-valve engines, which were attached to the same shaft 
with cranks at right angles to each other. The piston speed was 
350 feet per minute; mean effective pressure, 323. The sudden 
termination of the compression curve with a descending hook sug- 



Diagram No. 10. 

gests leakage of the piston or valve. The more rapid fall of the 
expansion curve than theory requires, strengthens this supposition, 
and points to the piston as the source of the trouble. The rise of 
counter-pressure in the middle of the return stroke is due to the 
reaction of the exhaust of the other engine. 



Diagram No. 11. 


Diagram No. II was taken from an engine, 18 x 36, in a mill 






300 


THE ENGINEER’S HANDY-BOOK. 


in Detroit, Michigan. The cut-off was effected by a special cut¬ 
off valve above the steam-chest, operated by a Kendall’s patent 
governor, which varies the throw and advance of an eccentric 
on the shaft by an arrangement similar to that of the link-motion 
of a locomotive. The most striking defect is the extremely late 
induction, showing a displacement of the eccentric, leading to a 
loss of about one-sixth of the stroke. The exhaust is too late, 
evidently from the same cause. 



Diagrams No. 12. 


Diagrams No. 12 were 
taken from a Brown auto¬ 
matic cut-off engine on ex¬ 
hibition at the Centennial 
Exposition. Diameter of 
cylinder, 15 inches; stroke, 
38; revolutions, 65; scale, 
30 lbs. They show wonder¬ 
ful conformity to theoreti¬ 
cal requirements, and that 
the engine and indicator 
must be in the most perfect 
order to produce such cards. 
The unusually sharp cut¬ 
off corners are due to a cer¬ 
tain extent to the fact that 
the induction and cut-off 
valves are of the gridiron 
type, and that the indicator 
is of an improved pattern, 
with exceptionally light 
moving parts; but neverthe¬ 
less there is an air of sus¬ 
picion about them, that will 
leave doubts of their gen¬ 
uineness in the minds of in¬ 


telligent engineers who understand the action of the valves of 


steam-engines. 


THE ENGINEER’S HANDY-BOOK. 


301 



Diagram No. 13 was taken from a John Cooper engine, built 
under the Babcock and Wilcox patent, at Mount Vernon, Ohio. 
Diameter of cylinder, 20 inches; stroke, 36 inches; boiler-press¬ 
ure, 55 lbs. per square 
inch ; speed, 60 revolu¬ 
tions per minute; scale, 

30 lbs. per square inch. 

It shows no imperfec¬ 
tions worthy of note, ex¬ 
cept the imperfect re¬ 
tention of the compres¬ 
sion-pressure, owing un¬ 
doubtedly to leakage 
either of the piston or 
slide valve. Such a de¬ 
fect is a very common 
one, and may appear 
when no other evi¬ 
dences of leakage exist, 
in which case it is prob¬ 
able that, if the com¬ 
pression escapes by the 
piston, the leakage ex¬ 
ists at the end of the 
stroke, or, if it escapes 
by the valve, only the 
portion which retains 
the compression-press¬ 
ure fits imperfectly. In 
the present case the 
compression curve com¬ 
mences promptly, but 
succumbs completely, and falls again before admission, show T - 
ing that the leakage commences suddenly near the end of the 
stroke. , 

26 1 ***** ‘ jU: 



302 


THE ENGINEER’S HANDY-BOOK. 


Diagram No. 14 was taken from a 9 x 15 high-pressure single 
slide-valve engine. Speed, 190 revolutions per minute; scale, 40; 



Diagram No. 14. 


clearance, 6’4 per cent.; mean effective pressure, 41 lbs. It will be 
noticed that its events occur late, which defects arise from counter¬ 
pressure, indicating obstructed exhaust and imperfect rise in the 
compression-pressure, suggesting leakage of either the valve or 
piston by which the compression-pressure has escaped. 



Diagram No. 15. 

Diagram No. 15 was taken from the same engine. Its defective 
performance, as shown by its late cut-off', late and insufficient ex- 









THE ENGINEER^ HANDY-HOOK. 


303 


haust, and its excessive counter-pressure, all tending to extrava¬ 
gant fuel consumption, speak louder than words of the vital import¬ 
ance of an intelligent use of the indicator by engine builders, par¬ 
ticularly when perfect¬ 
ing new designs and 
constructions. The 
counter-pressure was 
partly due to a con¬ 
tracted exhaust-nozzle 
used to create draught; 
but, even if it had had 
ample exhaust capac¬ 
ity at all points ex¬ 
cept at the nozzle, the 
counter-pressure cre¬ 
ated by that ought not 
to have exceeded one 
or one and a half to 
two pounds per square 
inch. 

Diagram No. 16 is 

an exact transfer from 
two diagrams taken 
separately from the 
same end of the cylin¬ 
der of an automatic 
cut-off engine. The 
dotted lines represent 
the card made by the 
Richards, while the 
plain lines represent Diagram No. 10. 

that made by the Thompson, indicator. A comparison reveals 
the fact that the correct average pressure cannot be ascertained 
from a diagram which is distorted by vibration, and also that its 
indications are deceptive as to admission, cut-off, and compression. 







304 


THE ENGINEER’S HANDY-BOOK. 



Diagrams Nos. 17 and 18 were taken respectively from the high- 
and low-pressure cylinders of the compound engines of the steam¬ 
ship Pennsylvania, of 
the American Line, 
built by Cramp & 
Sons, marine engi¬ 
neers and naval archi¬ 
tects of Philadelphia; 
speed, 58*3 revolutions 
per minute. The dia¬ 
grams present no de¬ 
fects ; the slight dif¬ 
ference in the mean- 
pressure of the two 
ends of each card (as 
in the case of all ver¬ 
tical engines) is due 
to the unbalanced 
weights of the recip¬ 
rocating parts. 

The theoretical 
clearance is about 10 
per cent.; and, as this 
is probably not far 
from the actual, the 
expansion curves show 
very correct perform¬ 
ance. The amount of 
vacuum shown is 10 to 
10 ^- lbs., which is above 
the average of marine 

Diagram No. 17. 

engines. 

As these engines are said to be more economical than any* 
heretofore used on ocean steamers, a calculation of their theoret¬ 


ical economy will not be without interest. Taking the steam used 






THE engineer’s HANDY-BOOK. 305’ 

» > 



by the small cylinder as the measure of consumption, the first 
process is to find for it the equiv¬ 
alent of the mean-pressure acting- 
on the large piston. The area 
of the small cylinder is 2574T975 
square inches, and that of the 
large one is 6379*4238 square 
inches. The M. E. P. of the 
small cylinder is 33*25 lbs., and 
that of the other 9*25 lbs. The 
rule is to multiply the area of 
the large piston by the mean- 
pressure acting on it, and divide 
the product by the area of the 
small piston. But, in the pres¬ 
ent case, it will involve less labor 
to perform the division first, 
that is, to divide the area of the 
large piston by that of the small 
one, and multiply the quotient 
by the M. E. P. of the large one. 

Thus, 6379*4238 -f- 2574*1975 x 
9*25 = 19*33 lbs., which, added 
to the M. E. P. of the small cyl¬ 
inder/ (33*25 -f 19*33 = 52*58 
lbs.), gives for it the equivalent 
of both, 52*58. Then the vol¬ 
ume of the average terminal (28 
lbs.) being 895, the calculation 

859*375 


will be as follows 


895 X 52*58 
= 16.2 lbs. From this the de¬ 
duction for compression will be 
about 3 per cent., or *48 lbs., leaving (16*2 — *48) 15*70 lbs. per 
I. H. P. per hour, which justifies theoretically the claim made 


26 * 


U 






306 


THE ENGINEER^ HANDY-BOOK. 


for these engines. The engines of the four steamships of this line 
gave very similar diagrams. 

Diagrams Nos. 
19 and 20 were 
taken respective¬ 
ly from the high* 
and low-pressure 
cylinders of the 
compound en¬ 
gines of the 
steamship St. 
Paul, built by 
Cramp & Sons, 
of Philadelphia, 
on her trial trip, 
and now plying 
between San 
Francisco, Cal., 
and Alaska. 
Scale of high- 
pressure cylinder 
30 lbs., of low- 
pressure cylinder 
12 lbs., per square 
inch. The data 
are as follows : 
steam, 67 lbs.; 
revolutions per 
min., 74; cut-off, 
*25 ; vacuum, 26 ; 
indicated horse¬ 
power of high-pressure cylinder, 262*5; of low-pressure cylinder, 
265*63; total, 528T3. Mean effective pressure of high-pressure 
cylinder, 43*125; of low-pressure cylinder, 14*25 lbs. The termi¬ 
nal-pressures, as shown by the diagrams, are as follows: The mean 



Diagram No. 19. 



THE ENGINEER’S HANDY-BOOK. 


307 


terminal-pressure of both ends of the high-pressure cylinder is 47 
lbs. (above vacuum); volume, 550. Of the low-pressure cylinder is 
11*25 lbs. above vac¬ 
uum ; volume, 2100. 

The equivalents for 
each cylinder of the 
combined power of 
both are as follows: 

For the high-press¬ 
ure cylinder, 43*125 
+ 43*64 = 86*765. 

For the low-pressure 
cylinder, 14*25 -f 
14*082 = 28*332. 

From these data, the 
calculation of the 
theoretical rates of 
water consumption 
will be for each cyl¬ 
inder as follows: For 
the high-pressure 

.. . 859*375 

ey " lder 86-765x550 
= 18 lbs. per indi¬ 
cated horse-power 
per hour. For the 
low-pressure cylin- 
859*375 

< ei ’28*332 x 2100 
14*44 lbs. indicated 
horse - power per 
hour. 

The maximum compression-pressures of each are so nearly 
equal to the terminal, that no correction for clearance and cushion 
need be made. The diagrams indicate good performance in all 










308 


THE ENGINEER’S HANDY-BOOK. 



Diagrams No. 21. 

Diagrams No. 21 were token from the simple surface-condensing 
engine of the steamship Vera Cruz, of Alexander’s Line, on her 


respects, the lack of smoothness in the lines being presumably 
due to the tremulous motion of the vessel. 







THE ENGINEER’S HANDY-BOOK. 


309 


thirty-ninth voyage from New York to Havana. Diameter of 


cylinder, 48^ inches; stroke, 6 feet; speed, 60 revolutions, or 720 
feet per minute; scale, 30 lbs. per inch. The boiler-pressure, which 
is represented by the lines above the diagram, was 72 lbs. per 
square inch; vacuum, 23 inches, the equivalent of which is rep¬ 
resented by the dotted line V V. The full line below represents 
a perfect vacuum. The theoretical expansion curves are the adia¬ 
batic curves, calculated from the table of volumes on pages 39 
and 43 of Roper’s Hand-Book of Land and Marine Engines. The 
calculations are as follows : 

Assuming the clearance to be 5 per cent., the mean-pressure of 
the theoretical diagram around the diagram B , which is based on 
the line V V, will be 32'8 lbs. The mean effective pressure of 
actual diagram B, 28*5 lbs. Percentage realized of the full theo¬ 
retical value of the boiler, terminal, and condenser pressures, 


28*5 x 100 
32*8 ” 


= 86 - 88 . 


Parallel calculations for the diagram Tgive 


the following: 

Mean-pressure of theoretical diagram, . 
Mean effective pressure of actual diagram, 


Percentage realized,; ^ ~ ~ ~ = 85*68. 

The mean of both ends is as follows: 

Mean-pressure of theoretical diagrams, 

Mean effective pressure of actual diagrams, 

-d . r j 27-875 x 100 Q 

Percentage realized,--— oo'o. 

oZ'o 


31-8 lbs. 
. 27*25 lbs. 


. 32*3 lbs. 
27-875 lbs. 


The area of the cylinder being 1847*45, and the piston speed 

720 feet per minute, the horse-pow r er value, or the horse-power for 

each pound of mean effective pressure, is calculated as follows: 

1847*45 x 720 : *' . J v 

- ouoii AA-— 40*3. The mean effective pressure being 27,875 

: .33000 t . $ t muuD.fiV lo dviaufoxa t diu8aoiq-flJi9M 

lbs., the tqtal horse-power e is 27,£75 X 40*3 1123*36. The ter¬ 

minal-pressure is 13 lbs., the volume of which is 1842, and the 







310 


THE ENGINEERS HANDY-BOOK. 


theoretical rate of water consumption will be found as follows: 


859375 

1842 x 27*875 


= 16*74 lbs. per indicated horse-power per hour. 


The compression-pressure so nearly equals the terminal, that 
no correction for compression and clearance is necessary. The dia¬ 
grams are in nearly all respects excellent; the curves, allowing 
for the unsteadiness which is apt to characterize diagrams taken 
from ocean-steamship engines, are remarkably correct; the engine 
was fitted with Corliss valves. The difference of about 2| lbs. 
between the vacuum attained in the condenser, V V, and that at¬ 
tained in the cylinder is a circumstance which is almost insepa¬ 
rable from such a high piston speed. A comparison of the rate of 
water consumption with that of such others as have been cal¬ 
culated, will be instructive, particularly with reference to the rel¬ 
ative economic merits of simple and compound engines, a question 
which is yet unsettled. A comparison of the foregoing calculation 
with the ordinary or long process will be instructive, as showing 
the correctness of the short method and the vast amount of labor 
saved by it, especially when dealing with large engines. 

Thus, 720 feet per minute X 60 X 12 = 518,400 inches per hour, 
which, multiplied by 1847*45, (area of piston,) = 957,718,080 cubic 
inches per hour, as the displacement of the engine. 

Then, 957,718,080 -f- 27*648 (cubic inches of water per pound) 
-i- 1842 (volume of 13 lbs. terminal) = 18,805*476 lbs. of water 
as its total theoretical consumption of water per hour; this -s- 
1123*36 (the indicated horse-power) = 16*74 lbs. per indicated 
horse-power per hour, as before. 


In making a complete analysis of diagrams, a statement of the 
mean effective pressure, exclusive of vacuum and that due to the 
vacuum, ought to be given separately. Thus: 

Mean-pressure, exclusive of vacuum, * . . 19*375 lbs. 

Mean-pressure due to vacuum, > , . , 8*5 lbs. 

Percentage of power due to vacuum, . • , 30*5, 



THE ENGINEER^ HANDY-BOOK. 


311 



Diagrams No. 22 were taken from the same engine as diagram 
No. 21, on the 
steamer’s forty- 
fourth return voy¬ 
age to New York 
from Havana. It 
represents con¬ 
siderably lighter 
load than diagram 
No. 21, and shows 
the attainment of 
a better vacuum, 
is more perfect in 
its lines, and is 
equally correct 
in its expansion 
curves. The line 
above the dia¬ 
grams represents 
the boiler-press¬ 
ure. The calcu¬ 
lations are as fol¬ 
lows : Mean ef¬ 
fective pressure 
of diagram B, 17 
lbs. Mean effec¬ 
tive pressure of 
diagram T, 19*5 
lbs. Mean of the 
two, 18*25 lbs. Diagrams No. 22. 

Terminal-pressure of bottom diagram, . . .6* lbs. 

Terminal-pressure of top diagram, . . . .7* lbs. 

Mean of the two,.6*5 lbs. 

Taking 3600 as approximately the volume of 6*5 lbs. pressure, 
the rate of water consumption will be 13*08 lbs. per indicated 








312 


THE ENGINEER'S HANDY-BOOK. 


horse-power per hour, which, if equalled, has never been exceeded 
by any other engines in this country, either simple or compound. 

Diagrams Nos. 23 and 24 were taken from the simple surface- 
condensing engines of the steamship Knickerbocker, of Crom- 



Diagram No. 23. 

well’s line, and running between New York and Boston. Many 
of the conditions could not be ascertained, but the mean effective 



Diagram No. 24. 

pressure of B appears to be about 29 lbs., and of T, 19 lbs. The 
calculations of. the rate of water consumption give for the card, 
B, 13*74 lbs., and for T, 15'5d. These very low rates are to some 
extent due to the very perfect vacuum attained. With the excep- 






THE ENGINEER'S HANDY-BOOK. 


313 


tion of the tardy induction, or deficient lead, as indicated by the 
inward inclination of the induction line, and the great difference 
in the work represented by the two, they are very perfect. And 
since both features may have been purposely introduced, the 
former to secure smooth running and the latter to compensate for 
unbalanced weight, etc., they should not be hastily pronounced 
faults of adjustment. 


Diagrams No. 25 present a case of extremely difficult analysis, 
as none of the conditions under which they w T ere taken could be 



Diagrams No. 25. 


ascertained. The left hand one shows tardy induction, by the in¬ 
clination of the admission line to the right. From A to I) } as 
will be observed, the pressure -falls -considerably; but it does not 
appear that the -cut-off* has taken place, as the-curvature of the 
line is upward, which is- never the case with a true expansion 
curve." From D -to E,> it will be seen, the pressure rises slightly, 
which fenders it evident that the steam cannot have been cut bff 


at any point previous to : E, unless for ah instant,* after' tohieh 1 it 1 
was readmitted. Supposing the lihe 1 td 1 correctly represent • the" 



314 


THE ENGINEER’S HANDY-BOOK. 


actual pressure on the piston, the most probable cause of the rise 
in the curve is, that the steam was admitted during the entire 
stroke to E, but not with sufficient freedom to maintain the press¬ 
ure when the piston travel was greatest, or that the connecting- 
pipe between the cylinder and the indicator was long and tortuous. 
The right hand diagram is not so peculiar, as it shows a hori¬ 
zontal steam-line and a tolerably well defined point of cut-off, C\ 
and expansion curve. In both the exhaust is much more free and 
prompt than the induction. The best vacuum was obtained at 
the beginning of the return stroke, F F, after which the lines 
undulate in a manner not easily accounted for, without an inti¬ 
mate knowledge of the construction of the engine and the con¬ 
ditions attending it. 

Diagrams Nos. 26 and 27 were taken from the simple condensing 
engine of the steamboat Mary Powell, plying between New York city 
and Albany, which has exceeded in point of speed any other steam 
craft on American waters, or in Europe, so far as can be ascertained, 
making 25 miles per hour between those points with perfect ease. 


Diameter of cylinder, ..... 

. 72 in. 

Stroke of piston, ...... 

12 ft. 

Diameter of piston-rod,. 

. 8 in. 

Diameter of air-pump, .... 

. 40 in. 

Stroke of the air-pump, ..... 

. 62 in. 

Very few data could be ascertained, but it seems 

that the M. E. 


P. of the top diagram was ..... 22‘02 lbs. 

Of the bottom, ...... 22*23 “ 

Mean of both,.22*13 “ 

Terminal of top, . . . . . 13*5 “ 

Of bottom,.18* “ 

Mean of both,. ..15*75 “ 

Theoretical clearance of top, . . . .12 per cent. 

Theoretical clearance of bottom, . . . 17 “ “ 

The water consumption appeared to be about 24*62 lbs. per 
horse-power per hour. The bottom card has the more compres¬ 
sion. The size and speed of the engine could not be ascertained. 


THE ENGINEER’S HANDY-BOOK. 


315 



The Powell is a splendid specimen of the American beam-en¬ 
gine river-boat which some years ago were so great favorites on 


Diagram No. 20. Diagram No. 27. 

account of the great speed they were capable of developing, but 
which are fast disappearing, and being superseded by another class 
of engines, on account of inherent defects in their arrangement. 







316 


THE ENGINEER’S HANDY-BOOK. 


Formula for Finding the Theoretical Clearance when 

the Scale is known. 


* 



From two points in the expansion curve, as A B, the former 
as early and the latter as late as possible consistent with the cer¬ 
tainty that both 
are in the expan¬ 
sion curve, draw 
the vertical lines, 
A D and B C, at 
right angles to 
the atmospheric 
and vacuum lines 
and the horizon¬ 
tal lines, A Oand 
B D, forming the 
parallelogram, A 
C D B. Then, 
through C D 
draw a diagonal 
line, continuing 
it downwards till 
it intersects the 
vacuum line at 
E, and from this 
point draw a ver¬ 
tical line, which 
will represent the 
clearance. It will, 
in the majority 
of cases, indicate 
more clearance 
than actually ex- 
saitb lodjoni :E>iagram;No; 28. i>a& ^aiiasqqi: i 8 ts; but if, as is 

sotnetimes the ease with large engines of good construction and 




THE ENGINEER'S HANDY-BOOK. 317 

in good condition, the diagram agrees closely with exact theory, 
the clearance thus shown will be less than the actual. 

On theoretical grounds, thlre should be no clearance at all, as 
any space between the cylinder-head and the piston at the end of 
the stroke must be filled with steam. But in practice it is impos¬ 
sible to dispense with it, since any wear of the parts must alter 
the stroke, and foreign substances, such as grease or water, may 
find their way into the cylinder. The loss resulting from clearance 
in cylinders may be lessened by judicious design, since, if com¬ 
pression takes place as the piston approaches the end of its stroke, 
it serves to raise the temperature of the steam enclosed, reduces 
the quantity of new steam required, and brings the momentum 
of the piston to rest, thereby lessening the shock on the crank. 

Formula for Finding the Seale of a Ilia gram when the 

Clearance is Jen own. 

Draw a line representing the clearance ; then proceed, as before, 
to draw the parallelogram, A C D B, and continue its diagonal, 

C D, till it intersects the clearance line, as at E. From the near¬ 
est point to this point of intersection, generally below, (which, by * 
its distance from the atmospheric line, will represent the pressure 
of the atmosphere, according to one of the scales in use,) draw 
the vacuum line which fixes the scale. For instance, suppose the 
intersection occurs about T 7 g of an inch below the atmospheric 
line. The nearest point below that point at which a vacuum line 
can be located to correspond with any of the usual scales is that 
corresponding with the 30 lbs. scale, or a little less than ^ inch. 

If, however, there be reason to suspect that the actual scale varies 
from 30 to 40, (32, for instance,) this method will not determine 
it with certainty, but it will approximate it when the different 
scales used are known to differ from each other to the extent of 
10 to 20 lbs. per inch. No method can be relied upon when only 
a limited length of the expansion curve is available, or when it is 
much distorted by vibration, or other defects in the performance 

of the instrument. 

27* 


318 


THE ENGINEER^ HANDY-BOOK. 



Formula} for Finding the Horse-Fower of Steam-Engines 

by Indicator Diagrams. 

The custom of dividing the indicator card into ten ordinates 

lias been generally adopted by engineers because ten is the most 


Diagram No. 29. 


convenient number for a divisor, since the process of dividing by 
it consists merely of pointing off one decimal. The M. E. P. is 
ascertained by dividing the aggregate length of the ordinates by 
their number, and multiplying the quotient by the scale of the 
diagram. The following instructions will be found useful to per¬ 
sons unaccustomed to make the calculation. 

First. — Divide the card into ten equal parts, as shown by the 
dotted lines in the above diagram, after which draw a line exactly 
through the centre of each space, as shown by the full lines 1, 2, 
3, etc. Then draw the dotted line A A, representing the atmos¬ 
pheric line, also draw the full line V V, representing the zero, or 
vacuum line, which is equal to 14^ pounds, below the atmos¬ 
pheric line; then measure the card at the following points: 






THE ENGINEER^ HANDY-BOOK. 


319 


The initial-pressure as shown at. I. 

The pressure at the point of cut-off . . . . C.O. 

The terminal-pressure at. T. 

The pressure at the end of the cushion . . . C. 

Next measure the full lines, or ordinates 1, 2, 3, etc., with a 
slip of paper, marking with a sharp pencil or the point of a knife 
the length of each, until it contains the sum of all their lengths, 
which in this case will be found to be 11*75 inches; then, from 


11.75 

the mean length - ~ =1*175 


inches, and the mean-pressure 


ii 


ii 


ii 


ii 


a 


ii 


I. = 32*01 bs. 
C. 0. = 28*0 “ 
T. = 17*0 “ 

B. = 5*6 “ 

C. = 18*5 “ 

18*8 “ 


1*175 x 16 scale of the indicator = 18*80 pounds; the correct 
rendering of such a card would be as follows: 

Initial-pressure, (above zero) 

Pressure at cut-off 
Terminal-pressure 
Mean back-pressure 

Pressure at end of cushion (above zero) 

Mean-pressure 

Suppose the diagram to be taken from one end of a cylinder 
50 inches in diameter (with a stroke of 48 inches), making 50 
revolutions per minute, and the area of piston to be 1963*5 square 
inches, then 1963*5 x 18*8 = 36,913*8. This pressure acts on 
the piston throughout the stroke, 48 inches, 50 times a minute, 
and the work done on one side of the piston in each minute would 

48 

be 36,913*8 X 50 X — 7,382,760. Now, if another diagram were 

taken from the other end of the cylinder, and the measurements 
be the same, the total work done by the engine each minute would 
be 3000 — 447, indicated horse-power. 


Another Formula, 

In the analysis of diagrams in this work, the usual custom of 
dividing the diagram into ten ordinates has been departed from, 
because, in the first place, ten ordinates were not considered enough 
to insure accurate calculation; and, secondly, because, when the 


320 the engineer’s handy-book. 

number of ordinates is. made the same, or one-half, one-third, or 
one-fourth as many as there are pounds per inch in the scale 
of the diagram, the calculation is, if anything, simpler than the 
old process, since the sum of the ordinates, as measured on the 
strip of paper in inches, is the mean effective pressure at once, 
■when the number of ordinates equals the scale, and in other cases 
it bears the same relation to it that the number of ordinates does 
to the scale. Ten ordinates may be used, however, for such scales 
as are divisible by 10. 

Suppose the scale to be 60, and the number of ordinates 10, 
aud that the sum of their lengths is 7 inches. According to the 
former process, t 7 q — *7 X 60 — 42 lbs.; by the latter method, sup¬ 
posing the number of ordinates to be J of the scale, the process is 
simply 6x7 — 42; that is, the mean effective pressure would be 
six times the sum of the length of the ordinates, if the scale is six 
times their number. 



Diagram No. 30. 


Suppose the scale to be 40 lbs per inch, one-half of that num¬ 
ber, or 20 ordinates, as shown in the above diagram, are used; 
and suppose the sum of their lengths is found by the process of 
measurement above given to be 15 8 inches, then twice that num¬ 
ber will be the mean effective pressure in pounds per square inch, 
or 15*3x2 = 30*6 lbs. Suppose the cylinder of an engine is 20 




THE ENGINEER’S HANDY-BOOK. 


321 


inches in diameter, 40 inch stroke, running at a speed of 75 revo¬ 
lutions, or 500 feet per minute; the area of such a piston would 


, qiii£ • , , 314*16x500 _ 0 _ 

be ol4 lb square inches; hence, — —— — =4*727 horse-power 


for each pound of mean effective pressure. The latter being 30*6, 

then 30*6 x 4*727 = 14^656, the indicated horse-power. 

. • J 


What Indicator Diagrams Show, and How they Show it. 

The object of indicator diagrams is to show the pressure acting 
on the piston of the engine to which it is applied at all points, and 
also at what part of the stroke any change of pressure takes place. 

Indicator diagrams supply the means by which to calculate the 
mean effective pressure acting on the piston, which, together with 
the known area and speed of the piston, furnishes the factors from 
which to calculate the power of engines. 

Indicator diagrams show the steam-pressure by the height to 
which the pencil traces the line on the paper measured from the 
atmospheric or vacuum line. 

When the line representing the back-pressure in the diagrams 
of high-pressure engines shows more than one pound above atmos¬ 
phere, or, in low-pressure engines, two or three pounds more than 
the vacuum-gauge shows in the condenser, the diagram indicates 
undue back-pressure, and that there is evidently something wrong. 

The diagram shows whether the valves of a steam-engine are 
properly set or not, because, if there is too little lead, it will lean 
towards the exhaust. If the exhaust takes place too early, the 
point, D, in diagram No. 1, page 291, will be further from the end, 
/; whereas, if the exhaust closes too early, and, as a consequence, 
there is too much “cushion ” or “ compression,” it will be shown 
by the great distance of the point F from E. 

A diagram shows whether the pistou and valves are leaky or 
not; though it is often difficult to decide to which the leakage may 
be due, as the one neutralizes the other. But if the piston alone 
leaks, the effect will be a more rapid fall of the pressure during 

V 



322 


THE ENGINEER’S HANDY-BOOK. 

expansion than theory requires, and the back-pressure will be 
greater than if the piston was tight. If the slide-valve leaks, the 
effect on the diagram will depend on the point at which the leak¬ 
age occurs. It may leak at the ends, so as to keep on admitting 
steam after it covers the port; or it may leak at the bridges, and 
allow the steam to escape in advance of the exhaust. In the first 
case, the expansion line would fall less, and in the latter case 
more, than theory requires. 

A diagram shows whether the steam is throttled or not by the 
expansion curve falling below the boiler-pressure when the throttle- 
valve is wide open. 

A diagram shows the effect of small ports and small steam con¬ 
nections by the steam-line starting below boiler-pressure, and fall¬ 
ing before the closing of the cut-off. A pipe-diagram is the only 
reliable means of determining such defects. 

A diagram shows the effect of exhaust-lead, by the exhaust 
taking place before the end of the stroke is reached, as in nearly 
all the diagrams shown. 

A diagram shows that the indicator is out of order, or whether 
there is lost motion between the piston and the pencil lever, by 
indicating more back-pressure than actually exists. 

A diagram shows the point of cut-off, which may be termed 
the point of contrary flexure, that is, the point where the steam¬ 
line, B C, (explanatory diagram) changes its direction from a 
straight line to a curve. 

A diagram shows the state of the vacuum in the condenser, and 
whether too much or too little injection-water is used or not; but 
in this case it is less reliable than the vacuum-gauge. Too much 
injection-water can only be shown on the diagrams, by taking one 
first with the proper quantity, and another with the increased 
quantity, and calculating the power of each. If the extra power, 
required to pump out the extra water against the atmospheric 
pressure, more than counterbalanced the gain from the better 
vacuum, the conclusion would be that too much injection-water 
was used. 


THE ENGINEER’S HANDY-BOOK. 


323 


The Planimeter.* 

The planimeter, though not a recent invention, is almost un¬ 
known among engineers on this continent. This arises from the 
fact that, after its invention by Amsler, certain Swiss and German 
engineers got control 
of it, and limited the 
number that should 
be manufactured to 
their own individual 
necessities. It has 
never been manufac¬ 
tured in this country, 
or even offered for 
sale, until quite re¬ 
cently. Its functions 
are to measure indi¬ 
cator diagrams, ir¬ 
regular flues, steam 
passages, and. all dif¬ 
ficult or intricate fig¬ 
ures. It gives at 
once the area of a 
figure, without any 
second measurement 
being required, as the 
reading shown on the 
index counter gives the accurate area in square inches of the dia¬ 
gram over which it had been passed. 

To use the instrument, fasten the figure to be measured on a 
smooth board, and insert the point, A, in the board at any con¬ 
venient location; then make a mark on the diagram, as at D; 
next fix the movable point, B, at the place selected for starting; 
then turn the index-roller, C, round until O, on its periphery, 
corresponds with the 0 on the fixed vernier; then move it round 



* See page 65G. 






























































324 the engineer’s handy-book. 

the figure to the right, or in the direction of the hands of a watch. 
After it passes round the ent're figure, note how many whole 
numbers and subdivisions have passed the 0 on the vernier. The 
whole numbers will indicate the square inches, and the subdivisions 
tenths of square inches. If the 0 on the vernier falls between 
two subdivisions marked on the roller, read the number of square 
inches and tenths; then look on the vernier from 0 to 10, and find 
a mark which coincides with one on the rollers; the number of 
such mark, counting from 0 , will be the hundredths or second 
decimal place. 

Thus suppose that, in the figure measured, six subdivisions and 
part of another one have passed, and that the fourth mark on the 
vernier coincides with a mark on the roller, the area of the figure 
will be either 3*64, 13*64, or 23*64 square inches, according to 
whether the roller has made less than one, more than one, and 
less than two, or between two and three revolutions. The eye 
can readily decide as to the number of revolutions the roller has 
made, as it would be impossible to make a mistake of ten square 
inches in estimating the area of a figure within the capacity of 
the instrument. If the figure measured is an indicator diagram, 
it will nearly always be of less area than ten square inches, or at 
most only a trifle more, as the utmost capacity of the indicator is 
51 by 2f inches, or 15^ square inches; and they are very seldom 
worked beyond 4 by 24 inches. 

To find the mean effective pressure of a diagram from its area: 
Multiply the area by the scale, and divide the product by the 
length of the diagram in inches. Or divide the area by the length 
of the diagram, and multiply the quotient by the scale. The 
product is the mean effective pressure. 

Example. —Suppose the area is found as above to be 3*64 square 
inches, the scale 40, and the length of the diagram is 3| (3*875) 
inches; 3*64 x 40 -h 3*875 = 37*65 lbs., or 3*64 h- 3*875 x 40 = 
37*65 lbs. 

It will be seen that the labor of calculation will be facilitated, 
if, in taking the diagrams, care is taken to make them even inches 


THE ENGINEER’S HANDY-BOOK. 


325 


in length. But as the engineer will have to measure many not 
of his own taking, he should have a rule divided into hun¬ 
dredths. 

The annexed diagram was measured by the planimeter, and 
gives the following results: Area, T34 square inches; 1*34 multi¬ 
plied by 40 the scale -f- P98 = 18, the M. E. P. 



The area of a figure may be taken without placing the O on 
the roller opposite the O on the vernier; but in such cases it is 
necessary to take the reading before and after the tracing is made; 
the difference between the two readings will be the area of the 
figure. But it is preferable to place the O 's together. The mov¬ 
able point of the instrument may also be turned to the left, but 
in this case the reading must be subtracted from 10 to give the 
true reading. Each of the figures stamped on the roller indicates 
a square inch of area, and if a figure contains 10 square inches 
at the tracing-point, the roller will revolve once, and the O’s will 
coincide as at the start. 


Steam-Engine Economy. 

Hardly a “ decade ” has passed since the days of Newcomen, 
which has not witnessed the promulgation of some vague scheme 
which it was claimed would revolutionize the economical working 
of the steam-engine, or even do away with it entirely, and super- 

28 





326 


THE ENGINEER’S HANDY-BOOK. 

sede it by something else. Such wild schemes have invariably 
proved failures, as they must ever do, because there are some 
principles involved in the working of the steam-engine which, ac¬ 
cording to the natural order of things, can never be disproved. 
Consequently, those who intend to purchase steam-engines, or those 
who have capital invested in them, need entertain no fears that 
steam as a motive-power, and the steam-engine as a motor, will 
ever be superseded by anything else, while efficiency and economy 
are desirable objects to be attained. 

Nor has there been any new principle discovered in connection 
with the steam-engine since “Newcomen’s” time, as Watt, Horn- 
blower, and Oliver Evans knew just as much about the latent 
and sensible heat, temperature, and the elastic force of steam as we 
do; though they lacked the knowledge of applying it so econom¬ 
ically to the piston. This did not arise from ignorance of its 
properties so much as from the want of proper facilities to apply 
it. Nor is it at all likely that the steam-engine of the present 
day will ever be much improved upon in point of economy or 
efficiency, though it may be in point of durability. Good ma¬ 
terial, good tools, and perfect workmanship will go far towards 
the economical working of the steam-engine. It is a very notice¬ 
able fact, that no important improvement has been made in steam- 
engines of any kind within the past 15 years. To be sure, there 
have been many innovations introduced in that time, but upon ex¬ 
amination it will be discovered that, in nearly all cases, they were 
a revamp of things which had been used before, and abandoned for 
want of experience in their use and proper facilities for perfect¬ 
ing them. 

The mean effective pressure on the piston of a steam-engine is 
the exponent of the work performed. The term “ effective press¬ 
ure ” means the amount by which the total pressure behind the 
piston exceeds that which acts on the other side in opposition to 
its movement. The tennma^-pressure, or that at which the steam 
is released from the cylinder, is the corresponding exponent of the 
consumption of water by the engine or the cost of the power. 


THE ENGINEER’S HANDY-BOOK. 


327 


Hence, the best economy is attaiued when the mean effective press¬ 
ure is highest relatively to the terminal- pressure, and anything 
that will increase the former without correspondingly increasing 
the latter , or which will diminish the latter without correspond¬ 
ingly diminishing the former, will improve the economy. 

The amount of water consumed by an engine is the only in¬ 
telligible criterion of the economical results it is capable of pro¬ 
ducing. The amount of fuel consumed will depend upon the 
kind of boiler used, its condition as to dirt, scale, etc., the manner 
in which it is set and fired, the quality of fuel used, the draught, and 
numerous other conditions; while the amount of water used will 
depend entirely on the engine, provided that it is furnished with 
dry steam. The theoretical rate of water consumption, as deduced 
from the diagrams, can never be realized in practice. A certain 
amount will always be lost from condensation, leakage, and un¬ 
evaporated spray in the steam, for which no process of calculation 
can make allowance. 

Now admitting that the evaporative efficiency of steam-boilers, 
under the best conditions, is 8 pounds of water per pound of coal, 
providing the water consumption of an inferior type of engine is 
one cubic foot, or 624 lbs., it would require 7f lbs. of coal, or its 
equivalent in other fuel, to develop a horse-power; while an auto¬ 
matic cut-off engine would yield a horse-power with a water con¬ 
sumption of 20 lbs., and the consumption of less than 3 lbs. of 
good coal. If an inferior type of engine require the consumption 
of 5 lbs. of coal per horse-power per hour, and an improved 
engine produce the same power from a consumption of 3 lbs., the 
latter will effect a saving of 40 per cent, in fuel over the former. 
Such comparisons may be considered extreme, but this is not the 
fact, as such cases are quite common in every manufacturing dis¬ 
trict. A manufacturer at Detroit, Michigan, was induced to take 
out an engine, which he was influenced to believe was wasteful, 
and replace it with one that was represented to be very powerful 
and economical, and at the same time very cheap. The engine 
was represented by the manufacturers as being capable of de- 


328 


THE ENGINEER’S HANDY-BOOK. 


veloping 100 horse-power; but it utterly failed to come up to this 
representation. When the indicator was applied, it showed that 
the engine was developing only 60 horse-power. The coal con¬ 
sumption was found to be nearly 8 pounds per horse-power per hour. 

The great Lancashire (England) strike which occurred during 
the present year, and resulted in a loss to both employers and em¬ 
ployees of several millions of pounds sterling, was brought about 
by an attempt on the part of the manufacturers to reduce the 
wages of the operatives one cent on every ten yards of manufac¬ 
tured cloth. They defended their action on the ground that ten 
per cent, was all the profit they realized on their manufactured 
goods, and stated that, unless the operatives would submit to the 
reduction, they would have to discontinue their business. Never¬ 
theless, it had been well known for years, by reports made to the 
Lancashire Institute and the officers of the Midland Steam-Users 
Association, that there were thousands of steam-engines in that 
county, supplying power to factories, that were consuming from 
eight to nine, and in some cases ten and a half, pounds of coal per 
horse-power per hour, and yet the manufacturers could not dis¬ 
cover any “ leaky 

Before purchasing an engine or any other machine, there are 
some very important points to be considered which involve its 
commercial value, among which are, the amount which it would 
save or earn over another machine when in use, the time it would 
run without repairs, or the addition of any expenditure to its 
original cost. For these reasons, the conditions that should guide 
steam-users in the selection of engines are steady motion under 
varying circumstances, economy of fuel, and cost of maintenance. 
In the best types of the steam-engine, the principal expense, be¬ 
sides first cost, is fuel; but in inferior classes of engines, the cost 
of maintenance, such as lining up, and renewal of the different 
parts, increases annually, until in a few years the cost in many in¬ 
stances exceeds that of the fuel. It is to such considerations as 
these that steam-users should direct their attention when about to 
purchase steam-power, or replace a worn-out engine with a new one. 


THE ENGINEER’S HANDY-BOOK. 


329 


It has not always been the custom heretofore for those needing 
steam-power to purchase the most economical engines, but rather 
to buy for the lowest possible first cost, regardless of future main¬ 
tenance. Manufacturers of inferior steam-engines being aware 
of this, agree to sell an engine of a certain horse-power for a cer¬ 
tain price, perhaps 25 per cent, less than would be asked for a 
first-class machine. 

Many persons are under the impression that it requires more 
fuel to carry steam at 100 lbs. per square inch than at 50 lbs., which 
is evidently a mistake, for while it requires a slight addition of 
heat to raise it from 50 to 100 lbs., the expenditure is more than 
compensated for by the superior expansion of the steam. Of 
course, the radiation will be greater at a 100 lbs. pressure per 
square inch than at 50 lbs.; but this would be more than over¬ 
balanced by the saving in the consumption of steam; as steam at 
70 lbs. pressure per square inch will perform more than seven times 
as much duty as steam at 25 lbs. pressure. 

Another fact not generally as well known to engineers and 
steam-users as it ought to be, and which illustrates the benefits to 
be derived from expansion, is, that if an engine was taking steam 
Avhole stroke, or of the piston-stroke, with say 60 lbs. pressure 
per square inch, if the pressure is raised to 75 lbs. per square inch 
and cut off at f stroke, the engine would do the same amount of 
work. 

Location of Steam-Engines. 

There is no class of machines, save, perhaps, steam-boilers, 
that are so often injudiciously located as steam-engines; they are 
not unfrequently stowed away in out of the way places, without 
any regard being paid to their general appearance. This arises 
from the fact that persons consulted on such matters are allowed 
to locate steam-engines who are totally unfit to do so, on account 
of a want of that practical skill and experience that should be 
possessed by persons who undertake this duty. 

It is a mistake to locate an engine at the extreme end of a 
28 * 


330 


THE ENGINEER’S HANDY-BOOK. 


building or a long line of shafting, as, if the engine were located 
to divide the work equally, the strain on the section carrying the 
driving-pulley will be only one-half what it would be subjected 
to if the motion were communicated from one end. Engines are 
frequently so located for the ostensible purpose of economizing 
space; but, on examination of the surroundings, it will, in a ma¬ 
jority of cases, be found that no more space need be occupied by 
placing it in the centre, while there would be unquestionably a 
gain in the diminished friction. 

The Porter Allen High-Speed Engine. 

The cut on page 331 represents a front view of the Porter- 
Alien High-Speed Engine. As will be observed, the bed-plate is 
of the box form, the surface of which is raised near the centre 
line. The main-bearing being brought as near as possible to the 
centre line of the cylinder, the breadth and depth being of 
sufficient proportion to resist all strains, it presents no sharp 
angles that would be a source of weakness. In fact, the bed¬ 
plate was designed to secure absolute rigidity under high-piston 
velocity, and correspondingly high steam-pressures, as well as a 
support for the cylinder, thus making a self-contained horizontal 
engine. The cylinder is overhung from the front end of the bed¬ 
plate, without any support excepting that which is derived from 
the butt-joint which it forms with the housing, which admits of 
equal expansion on all sides, and prevents the possibility of getting 
out of line. The rigidity of these engines may be judged from 
the fact that not the slightest vibration is experienced under the 
highest piston-velocities and steam-pressures; nevertheless, when 
of necessity they have long stroke, there is a temporary support 
placed under the cylinder. 

The steam- and exhaust-chests are located on opposite sides 
of the cylinder, and cast in one piece with it; and the valves and 
seats are so arranged, that the removal of a small bonnet gives 
easy access to them. At the back of the steam-valves, an adjust- 


The Porter-Allen High-Speed Engine. 


THE ENGINEER’S HANDY-BOOK 


331 





































































































































332 


THE ENGINEER’S HANDY-BOOK. 


able pressure-plate is introduced ; this plate is made of a form 
which is calculated to resist the steam-pressure without deflection, 
and which is held against two inclined supports above and below 
the valve by a bolt screwed through the bottom of the chest. If 
this bolt is backed sufficiently, the steam will cause the pressure- 
plate to seize the valve. By turning the bolt forward, the pressure- 
plate is raised, and also moved away from the valve. The en¬ 
gineer can test each valve for leakage, by unhooking the disen¬ 
gaging hook, with which all these engines are provided, and work 
the valves by hand under steam-pressure by the starting-bar, while 
the assistant adjusts the bolt on the pressure-plate. If there has 
been no wear, the slightest movement of the bolt will cause the 
valves to be seized; but if there is any wear, it can be adjusted in 
a few moments. 

The exhaust-valves work under the pressure in the cylinder, 
and have short movements, each valve opening four passages for 
the release of the steam. The exhaust-valve seats are formed on 
* the covers of the chambers in which they work, and on which, 
also, the outlets are cast. They drain the bottom of the cylinder; 
they are very conveniently arranged for facing, adjustment, or re¬ 
pairs, and, by removing small bonnets, they may be taken out and 
replaced without any inconvenience. The release of the steam is 
one of the most remarkable features of these engines, as the link 
gives to the valve an admirable movement in every respect. The 
movement of the exhaust-valves being most rapid at the instant 
of release, the steam can be held to almost the end of the stroke, 
in consequence of the port opening to its full width at the instant 
the crank reaches the centre. 

The eccentric is forged on the shaft, which gives compactness, 
exactness of construction, and prevents it being shifted by acci¬ 
dent or design. The cylinder-heads are designed to receive the 
steam from the boiler, by which arrangement the clearance is re¬ 
duced to a minimum, and the economy of the engine increased. 
Great pains are taken with the crank- and cross-head pins, which 
are made of the best steel, and hardened. The connecting-rod 


THE ENGINEER’S HANDY-BOOK. 


333 


boxes are made of gun-metal or bronze. The upper and lower 
sides of the cross-head wrist are made flat. The crank-pins are 
of unusual diameter in proportion to their length, which brings 
the flattened connecting-rods close up to the faces of the accurately 
balanced disc-cranks. The construction of the marine pillow- 
block bearings is the result of much study, and presents many 
improvements over those to be seen in ordinary engines. The fly¬ 
wheels of these engines,like the cranks, are turned and accurately 
balanced, which insures smooth motion in the revolving and re¬ 
ciprocating mechanism. The regulator employed on these engines 
is what is known as the Porter governor, and is peculiarly adapted 
to this class of engines; and, in consequence of being more powerful 
and sensitive than any other governor in the country, it has been 
successfully applied to the controlling of the valves of other en¬ 
gines which no other governor in the market would regulate. 

The high-speed engine has not been heretofore appreciated in 
this country. As has been heretofore stated in this book, most in¬ 
telligent American engineers entertain the idea that there is 
nothing to be gained by running an engine at such high velocity, 
or employing extraordinary high pressure, because an engine, to 
run at such an extraordinary speed, needs to be built with great 
care, of first-class and expensive material, which increases its 
first cost. Besides, the cost of maintenance of such a machine is 
a continual source of annoyance. It is a well-established fact in 
mechanism, that haste, beyond a certain limit, induces waste, and 
that any attempt to force any machine, steam-engines and boilers 
included, induces rapid wear, deterioration, and eventually the 
destruction of the machine. The high-speed engine is one of the 
innovations that at different times, in the opinion of their advo¬ 
cates, were going to revolutionize the whole system of steam 
engineering. But their impracticability soon became evident, and 
they died out, only to give place to another set of schemes that 
have proved equally delusive. 





334 


THE ENGINEER’S HANDY-BOOK. 


Questions. 

What are the functions of the steam-engine indicator? 

How would you proceed to attach the indicator? 

Under what three heads may the particulars derived from an 
indicator diagram be classed ? 

State the conditions which are instrumental in determining the 
conformation of a diagram. 

Explain the points of difference between diagrams taken from 
automatic cut-off engines and those taken from slide-valve throt¬ 
tling engines. 

How would you draw the theoretical expansion curve geomet¬ 
rically? 

How would you trace a theoretical compression curve? 

From what circumstances does the inaccuracy of the theoretical 
curve arise? 

Describe the adiabatic curve. 

How would you locate the theoretical terminal pressure cor¬ 
responding to the actual cut-off? 

How do you account for the difference in theoretical correctness 
as shown by expansion curves of diagrams taken from different 
engines ? 

Why is the incorrectness of the expansion curve less with an 
engine heavily loaded than with a light load ? 

If the deviation of the expansion curve in diagrams (other 

things being equal) be found to be greatest when the water is 
high in the boilers, and the steam rapidly generated, to what 
cause might it be assigned ? 


THE ENGINEER^ HANDY-BOOK. 


335 


What is the most obvious lesson to be deduced from the facts 
in our possession in regard to the incorrectness of the curves of 
diagrams taken from large engines? 

What should be considered in indicator diagrams as indications 
of good construction and performance? 

How do you calculate the mean effective pressure? 

How would you space the ordinates ? 

How do you calculate the indicated horse-power? 

How do you calculate the theoretical consumption of water 
from indicator diagrams ? 

How do you make allowance for clearance and cushion? 

How do you estimate the effect of compression? 

What is the object of indicator diagrams ? 

What information do indicator diagrams supply? 

How do indicator diagrams show the steam-pressure in the cyl¬ 
inder ? 

When the line representing the back pressure in the diagrams 
of high-pressure engines shows more than one pound above atmos¬ 
phere, or in low-pressure engines more than two or three pounds 
than the vacuum-gauge shows in the condenser, what does the dia¬ 
gram indicate? 

How does the diagram show whether the valves are properly 
set or not? 

How does the diagram show whether the piston and valves are 
leaking or not ? 

How does the diagram show whether the steam is throttled or 
not? 


336 the engineer’s handy-book. 

How does the diagram show the effect of small steam ports 

and steam connections ? 

How does the diagram show the effect of exhaust lead? 

How does the diagram show that the indicator is out of order? 

How does a diagram show the point of cut-off? 

How does a diagram show the state of the vacuum in the con¬ 
denser, and whether too much injection-water is used or not? 

Sketch a diagram, and explain it. 

Show the points of excellence in a perfect diagram. 

Show the steam, atmospheric, and vacuum lines and the ex¬ 
pansion and exhaust curves. 

Define the adiabatic curve, and explain how it is obtained. 

♦ 

Define the asymptote lines. 

Define the term compression. 

Define the term cushion. 

Define the term clearance. 

Define the terms flexure and contrary flexure, and demonstrate 
them on the diagram. 

Define the term hyperbola, and illustrate it. 

Give the meaning of the term isothermal. 

Point out the ordinates on the diagram. 

Define the term parallelism. 

What is meant by the initial-pressure? 


337 


THE ENGINEER’S HANDY-BOOK. 

What is meant by the term mean effective pressure? 

What is meant by the term terminal-pressure? 

What is meant by the term scale in its application to the diagram ? 

Explain the functions of the spring in its relations to the indicator. 

Explain the meaning of I. H. P., N. H. P., M. E. P., and H. P. 

Explain the meaning of the term string. 

Define the term undulating. 

What are the use and functions of the dynamometer? 

What is the meaning of the letters B and l 1 which are fre¬ 
quently seen on diagrams? 

Define the term zero when applied to indicator diagrams. 

Give the formula for finding the horse-power of an engine from 
indicator diagrams. 

What are the functions of the planimeter? 

Explain the most correct method of using the planimeter. 

What is the exponent of the work performed by a steam-engine? 
For the meaning of the term mean effective pressure, see page 259. 

What is the best criterion of the most economical results which 
a steam-engine is capable of producing? 

Before purchasing a steam-engine or other machinery, what 
considerations ought to be taken into account? 

Is there any difference in the consumption of fuel required to 
carry steam at 100 lbs. pressure instead of 50 lbs. per square inch ? 

How should engines in factories be located? 

29 W 


338 


THE ENGINEER’S HANDY-BOOK. 


PART FIFTH. 


Condensers. 



The condenser is one of the most necessary and important ad¬ 
juncts of the low-pressure engine, as in 
the perfection of the vacuum produced in 
it by the condensation of the steam lies 
the economy of that class of machines. 
All the other parts of the engine may be 
modified, and many of them, in some 
cases, dispensed with, as in the trunk 
and oscillating engines. Even the air- 
pump, as has been shown in a former 
article, is not an absolute necessity; but, 
whatever changes a condensing engine 
may undergo, the presence of the con¬ 
denser is an imperative necessity. 

The two kinds of condensers in gen¬ 
eral use are known as the jet and sur¬ 
face. The surface condenser consists 
of an iron box, in which brass or copper 
tubes are inserted in tube sheets, simi¬ 
lar to those of a tubular steam-boiler, 
through which the water is forced by 
the circulating pump, for the purpose 
of condensing the steam. In some cases 
condensation is effected by bringing the 
exhaust steam in contact with the out¬ 
side of the tubes, the circulating water 
being on the inside; while in others the 
steam is exhausted into the tubes, and the circulating water 
distributed on the outside of them. There is no especial ad- 


End View of a Surface 
Condenser with the 
Bonnet removed. 








































































































THE ENGINEER^ HANDY-BOOK. 


339 


vantage in the former over the latter, nor vice versa , the ar¬ 
rangement being only a matter of taste. In the proportioning of 
either surface or jet condensers there appears to be great latitude 
in practice, but in the surface condenser a certain amount of cooling 
surface must be provided ; more than the required quantity is a waste 
of material, and incurs unnecessary weight and first cost, besides the 
extra time required to remove the air before starting. The objec¬ 
tion to a small condenser is, that in case the air-pump should fail to 
operate properly, the condenser would soon become choked with 
water; the best guide in such cases is practical experience. 

In the surface condenser, the cold water is lifted by a circulat¬ 
ing pump through a pipe in the ship’s side or bottom and forced 
through the tubes, and thence overboard. The number of times 
the water circulates, depends on the design and arrangement of 
the condenser. In some condensers it circulates once, in others 
twice, and in others three or even four times. In the cut on page 
338 the steam enters at A, and the injection-water at B, which 
returns through section C, re-returns through section D, and is 
forced overboard through E . F represents the hot well contain¬ 
ing the water of condensation, which is returned to the boilers by 
means of the boiler feed-pumps. 

The capacity of the circulating pumps of the best class of sur¬ 
face-condensing, compound engines is about 1 to 22 , or 1 cubic 
foot of circulating pump capacity to 22 feet in the low-pressure 
cylinder, and in the proportion of about 1 cubic foot of circulating 
pump capacity to 588 feet of cooling surface in the tubes of the 
condenser. The proportion of cooling surface in the best class of 
surface condensers is about 28 square feet of cooling surface to 1 
cubic foot in the low-pressure cylinder, or 62 square feet to the 
indicated horse-power. 

The advantages of surface condensers are, that they furnish 
fresh water to the boilers, (since the sea injection-water does not 
mingle with the water of condensation, thus obviating the loss in¬ 
duced by scale in the boiler,) that steam of any pressure can be 
pondensed, and that the vacuum is more perfect than in the jet 


340 


THE ENGINEER^ HANDY-BOOK. 


condensers. Their disadvantages are, extra weight and first cost, and 
that the tubes are liable to become leaky, and impair the vacuum. 
In case the tubes should become so leaky as to be beyond remedy, 
the surface condenser may be converted into a jet condenser by 
admitting the exhaust steam and injection-water above the tubes; 
but the jet condenser cannot be changed into a surface condenser 
under any circumstances. 

The tubes of surface condensers are made of brass or copper, 
generally about | of an inch in diameter. They were formerly 
riveted into the heads or tube sheets, but in consequence of the 
lightness of the material of which they are composed, and of its 
great limit of expansion, they soon became loose and leaky, as a 
result of which riveting was abandoned. They are now generally 
made tight by means of some fibrous material, such as cotton or 
India-rubber, but more recently by brushings of kiln-dried or con¬ 
densed wood. 

The jet condenser consists of an iron pot or shell, into which 
the steam is exhausted. The water rises through a pipe in the 
ship’s side, by the pressure of the atmosphere, and is distributed 
by a rose, an arrangement similar to the nozzle of an ordinary 
garden watering-pot, which, as it frequently became choked by 
substances carried in by the injection-water, was abandoned. The 
distribution of the water is now effected by allowing it to strike a 
cone in the cover of the condenser. 

The capacity of jet condensers may be from to the ca¬ 
pacity of the steam-cylinder, or it may be of the same capacity as 
the air-pump. The advantages of a jet condenser are, that it is 
light, simple, and inexpensive; and its disadvantages, that the 
saline matter contained in the injection-water is carried into the 
boilers, which lessens the economy of fuel, and that steam of a 
very high pressure cannot be successfully condensed in it. Should 
the condenser become so impaired, as to be incapable of creating a 
vacuum, the connection between the condenser and the engine 
may be separated, and the engine allowed to exhaust into the at¬ 
mosphere, when it becomes a non-condensing engine. 


341 


THE ENGINEER^ HANDY-BOOK. 

A snifting-valve is fixed on the condenser to allow the air and 
water to escape when the condenser is blown through. The vac¬ 
uum in the condenser keeps it closed, and, in the event of a great 
head of water, or pressure in the condenser, the valve will ease 
up and allow it to escape. 


TABLE 

SHOWING THE FORCE WITH AVHICH THE UNCONDENSED STEAM ARISING 
FROM THE WATER IN THE CONDENSER RESISTS THE ASCENT OR DESCENT 
OF THE PISTON, ACCORDING TO ITS TEMPERATURE. 


Temperature, 

Fahrenheit. 

Force in 
Inches of 
Mercury. 

Pounds per 
Square Inch. 

Temperature, 

Fahrenheit. 

Force in 
Inches of 
Mercury. • 

Pounds per 

Square Inch. 

32 

0-200 

o-ioo 

130 

4-36 

2-17 

40 

0-250 

0-128 

135 

5-07 

2-52 

50 

0-360 

0-181 

140 

5-77 

2-88 

55 

0-416 

0-215 

145 

6-60 

3-28 

60 

0-516 

0-260 

150 

7-53 

3-74 

65 

0-630 

0-311 

155 

8-50 

4-22 

70 

0-726 

0-361 

160 

9-60 

4-76 

75 

0-860 

0-428 

165 

10-80 

5-37 

80 

1-01 

0-505 

170 

1205 

6-04 

85 

1 T 7 

0-585 

175 

13*55 

6-75 

90 

1-36 

0-680 

180 

15-16 

7-58 

95 

1*58 

0-805 

185 

16-90 

8-47 

100 

1-86 

0-900 

190 

1900 

9-50 

105 

2-10 

1-07 

195 

21 T 0 

10-58 

110 

2-53 

1-26 

200 

23-60 

11-81 

115 

2-82 

1-43 

205 

25-90 

1301 

120 

3-30 

1-50 

210 

28-88 

14-43 

125 

3-83 

1-902 

212 

30 - 

15 - 


The temperature of the water in the hot wells of surface-con¬ 
densing engines is generally about 100° to 110° Fah. A higher 
temperature would affect the vacuum and injure the air-pump 
29 * 

















342 


THE ENGINEER’S HANDY-BOOK. 


valves, while a lower temperature would cool the cylinder, and 
cause a waste of fuel by the condensation of the steam. A very 
low temperature causes increased consumption of fuel, while a very 
high one causes a loss of power, owing to the back pressure in¬ 
duced by the uucondensed vapor in the condenser, which will be 
shown by the vacuum 7 gauge. 

In the jet condenser, when the bilge-injection is opened, the air- 
pump draws off the air from the pipe, when the air in the ship, 
pressing on the surface of the bilge-water, forces it up the pipe 
into the condenser. In the surface condenser the circulating 
pump creates the vacuum, and the air presses the water up. 

In a jet condenser, if the injection-water is not shut off when 
the engines are stopped, the condenser will be filled with water, 
and, if not cleared before the engine is started, may cause serious 
damage to the cylinder or condenser. 

Relative Quantity of Injection-Water Required to Con¬ 
dense a Certain Volume of Steam. 

The weight or quantity of injection- or condensing-water re¬ 
quired for a given weight or volume of steam depends upon 
several conditions: 1. The pressure at which the steam is ex¬ 
hausted. 2. The absolute pressure existing in the condenser after 
the vacuum has been formed. 3. The temperature at which the 
injection-water enters the condenser. While the first and second 
conditions vary but slightly with uniform load and steam pressure, 
the third will vary with the season, and even with the weather; 
consequently, more condensing-water is required in summer than 
in winter. But the average amount may be illustrated as 
follows: 

Example. — Suppose the pressure in the cylinder at release or 
exhaust be 5 lbs. above atmosphere, and the absolute pressure in 
the condenser, after vacuum is formed, be 2 lbs., corresponding to 
a vacuum of 26 inches of mercury. Each pound of steam ex¬ 
hausted at 5 lbs. above atmosphere contains 1183 thermal units, 


THE ENGINEER’S HANDY-BOOK. 


343 


and the thermal units per pound of condensation at 2 lbs. abso¬ 
lute pressure in the condenser are 126. Hence the thermal units 
to be absorbed by the condensing-water are 1183 —126 = 1057. 
Suppose the temperature of the injection-water be 80° Fah., then 
each pound of condensing-water takes up 126 — 80 = 46 thermal 
units; and pounds of condensing-water per pound of steam con¬ 
densed become — 23 nearly. Suppose, again, that the tem¬ 
perature of the injection-water be 40° Fah., then each pound of 
condensing-water takes up 126 — 40 = 86 thermal units, and 
pounds of condensing-water per lb. of steam condensed are 

-jj|- = 12*3 lbs., from which it will be seen that the average pro¬ 
portion ot condensing-water to the water of condensation is about 
as 18 to 1. 

Rule for finding the cooling surface in the tubes of surface con¬ 
densers. 

Multiply the circumference of one tube in inches by its length 
in inches; then multiply that product by the whole number of 
tubes, and divide by 144. The quotient will be the number of 
square feet of cooling surface in the tubes. 

The tubes of surface condensers frequently become foul on 
the inside, owing to the grease used to lubricate the cylinder being 
carried over with the exhaust steam, and they become foul on the 
outside by the saline matter in the injection-water adhering to 
them. There are various ways of cleansing them, one of which 
is to admit steam of a high pressure from the boiler to the con¬ 
denser. Another is to fill the condenser with a strong solution 
of soda of potash, but in both cases care must be taken not to 
destroy the packing round the tubes, of whatever material it may 
be composed. If the tubes are packed with wood, and allowed to 
become too hot by the action of the steam, they will become 
charred and drop out; if packed with India-rubber, they will be 
destroyed by too high a temperature; if the solution of potash 
used to clean them is too strong, they are liable to be ruined. 


344 


THE ENGINEER’S HANDY-BOOK 



ENGINE 




: . _ J 


MRFL0\V 




A shows the steam-pipe; B, the stop-valve; C, tlie exhaust-pipe; E, the 
annular head into which the condensing-water is thrown through the 
pipe, G, and by the arrangement of which the water is formed into a 
sheet ; FF shows the two inverted nozzles through which the condensing- 
water escapes into the hot well, H. 













































































































345 


THE ENGINEER’S HANDY-BOOK. 

The Injector Condenser. 

The cut on the opposite page represents the injector condenser,so 
called because its action is similar to that of the Giffard boiler feed- 
injector. It consists of two conoidal nozzles, joined by a straight 
neck, and swelled at the upper end for the junction of the water- 
nozzle. Within is the exhaust-steam nozzle, which forms within 
the condenser a narrow, annular space for the entrance of the con- 
densing-water. The sides of the condenser (which are parab¬ 
oloidal curves) are smoothly finished, as is the contracted neck 
below, to diminish the resistance of the water. When used in 
connection with a condensing engine, the air-pump may be dis¬ 
pensed with, as steam of atmospheric pressure will flow into a 
vacuum at the rate of 1600 feet per second. 

When the exhaust steam from the engine meets the thin film 
of water which enters by the annular space, it is instantly con¬ 
densed. As the water passes down, the contracting outline of the 
condenser gradually brings it to a solid jet in the neck below, 
through which it rushes with a velocity due to its pressure. The 
air which has entered the condenser with the water, or through 
leaky joints or stuffing-boxes, together with the uncondensed 
vapor, is thus drawn down into a contracting, hollow cone of 
water, until finally expelled through the neck. This latter being 
straight for a distance, is virtually the air-pump, having a solid 
piston of water moving at a high speed ; thus is the steam con¬ 
densed, and the vacuum formed by a single process, and with 
greater certainty than in any other way. The air and vapor 
having passed the contracted neck, enter the tapering nozzle 
below, and expanding therein are prevented from returning to 
the condenser above. 

The method of operation of the injector condenser when the en¬ 
gine is started is as follows: the exhaust steam expels the air from 
the exhaust-pipe and condenser ; then a jet of cold water from a 
pump or tank creates a vacuum, which may be maintained by a 
head of water of 10 feet fall. The discharge-water passes off* at 


346 


THE ENGINEER’S HANDY- BOOK. 

a temperature of 110° to 112°, when the vacuum is equal to 26 
inches of mercury. 

The advantages of the injector condenser are, that it is cheap, 
light, simple, and durable; that the injection-water is self-regu¬ 
lating ; that there is no possibility of the water being carried over 
iuto the cylinder; that, simply by the removal of a bonnet, the 
exhaust steam may be allowed to escape into the atmosphere, thus 
converting the engine from low to high pressure ; that the con¬ 
denser requires no foundation or any other attachment save an or¬ 
dinary pump to raise the water when there is not sufficient fall; 
and that the condenser can be attached to any engine in any lo¬ 
cality where the necessary supply of water can be obtained, which 
ranges from 22 to 25 times as much as that from which the steam 
would be generated. It is claimed that a saving of over 20 per 
cent, may be made where these condensers are used, while the first 
cost is trifling. 

Independent Condenser and Air-Pump. 

The annexed cut represents a very ingenious and convenient 
combined condenser and air-pump, designed by Edwin Reynolds, 
and manufactured by E. P. Allis & Co., Milwaukee, Wisconsin, 
to be used in connection with the Reynolds Corliss engine, and 
which can, in case of accident to the engine which drives the 
machinery, be used as an independent or auxiliary engine, which 
may be used while making repairs. A foot-valve is entirely dis¬ 
pensed with, and only bucket- and deli very-valves used. They 
are fitted up either with or without a steam-cylinder, and when 
the latter is dispensed with the air-pump is driven by a belt 
from the engine to the wheel, T; but when driven by the steam- 
cylinder a regulator is employed, which is not shown in the cut. 
The barrel, A, which is bored out on a line with the steam-cylinder, 
a , forms a cross-head guide, to which the steam-piston is attached. 
Four rods form a connection with the cross-bead of the air-pump 
below the crank-shaft. 

The head, B, shows the bonnet or cover of the valve-chamber, 


HANDY-BOOK 


347 


THE ENGINEER^ 



Independent Condenser and Air-Pump. 


Designed for the Reynolds Corliss Engine, and Manufactured by E. P. 
Allis & Co., Milwaukee, Wis. See description on pages 346 and 348. 
























































































































































348 


THE ENGINEER^ HANEY-BOOK. 


and the flange, C, the steam-pipe connection. D represents the 
bracket containing the valve-stem stuffing-box, the outer end of 
which forms a bearing for an oscillating valve, to the stem of 
which the crank, E, is keyed, which operates the steam-valve. 
The swell, F, constitutes the steam-ports from the valve-chamber 
to the end of the steam-cylinder. G shows an opening provided 
for getting at the stuffing-box of the piston-rod and oiling the 
cylindrical cross-head. The eccentric, H , gives motion to the 
steam-valve through the rod,i?, and crank, E. The crank I, which is 
slotted for the purpose of adjusting the length of the stroke, drives 
the force-pump, J, which may be used either as a lift and force, 
circulating, or boiler feed-pump, k represents the delivery- and K 
the suction-pipe. The pipe, M, is the injection-pipe; N> the suction 
for the force-pump, which takes its water from the pocket, S. The 
valve, L, is used to regulate the quantity of water admitted to the 
force-pump. The pipe, 0, is the overflow from the air-pump, which 
is in the centre of the condenser. The plate, V , covers a man-hole, 
through which access is had to the valves and piston of the air- 
pump. 

The Vacuum. 

If the cylinder of a steam-engine be filled with vapor, it cannot 
be said to be void of matter; but if the vapor is condensed, and 
the water from which it was vaporized drawn off, there would be 
created in the cylinder what is termed a “ vacuum,” or void space. 
The absolute pressure of steam is measured from zero, or perfect 
vacuum, and consists of the pressure indicated by the steam-gauge 
(which is known as pressure above atmosphere), added to the 
pressure of the atmosphere, as shown by the barometer. The 
latter is, for all practical purposes, a constant quantity for any 
given locality,* and may be roughly taken at 14*5 lbs., cor¬ 
responding to 29*50 inches of mercury. Vacuum-gauges are 
usually graduated to agree with the scale of the barometer, and 
the vacuum is usually stated in inches of mercury. To the steain- 


* See Table on page 498. 




THE ENGINEER’S HANDY-BOOK. 


349 


pressure, as indicated by the gauge, add 14*5 lbs. for total press¬ 
ure. Thus, if the pressure by gauge is 60 lbs., the total pressure 
is 74*5 lbs. Consequently, the total pressure oil the steam side, at 
any point in the stroke of the piston, is the pressure above the 
atmosphere plus 14*5 lbs., and the total pressure for the whole 
stroke is the mean-pressure above the atmosphere plus 14‘5 lbs. 
Thus, if the mean-pressure for whole stroke is 30 lbs., the total 
mean-pressure is 44-5 lbs.; and this 44‘5 lbs., whether the engine 
is condensing or non-condensing, is the variable factor in estima¬ 
ting the load on the engine. Now, if the engine be non-conden¬ 
sing, the 14’5 lbs. (pressure of the atmosphere) on the steam side 
of the piston is balanced by an equal atmospheric pressure on the 
exhaust side, and its effect is neutralized; but if the engine be 
condensing, a large proportion of the pressure of the atmosphere 
on the exhaust side of the piston is removed, and an equivalent 
portion of the pressure of the atmosphere on the steam side of the 
piston made to do useful work. With well-proportioned conden¬ 
sing apparatus, the pressure of the atmosphere on the exhaust side 
of the piston can be reduced nearly 90 per cent. 

TAB BE 


SHOWING VACUUM IN INCHES OF MERCURY AND POUNDS PRESSURE PER 

SQUARE INCH. 


Mercury. 

Pounds. 

Mercury. 

Pounds. 

2-037 

1 

16*300 

8 

4-074 

2 

18-337 

9 

6-111 

3 

20-374 

10 

8-148 

4 

22-411 

11 

10-189 

5 

24-448 

12 

12-226 

6 

26-485 

13 

14-263 

7 

28-552 

14 


The lower the temperature of the water leaving the condenser, 
the better the vacuum, and the more conducive to power, always 
30 














350 


THE ENGINEER’S HANDY-BOOK. 


supposing there be no air-leaks. AVatt found a temperature of 
100° in the water leaving the condenser more beneficial than 70° 
or 80°, supposing there be an abundant supply of cold water. It 
may be explained in this way. A better vacuum due to a tem¬ 
perature of 70° or 80° requires so much cold water in the con¬ 
denser, (which must afterwards be pumped out against the press¬ 
ure of the atmosphere,) that the gain in the vacuum does not 
equal the loss of power caused by the additional load on the pump. 
There is, therefore, a clear loss by the reduction of the temper¬ 
ature below 100°, if such reduction be caused by the admission 
of an additional quantity of water. 

The vacuum is maintained in the condenser by the action of the 
air-pump. A perfect vacuum cannot exist, and in the condenser 
of an engine there is always more or less pressure from imperfect 
condensation, and air passing in with the condensing-water. 

The vacuum is measured by inches in the height of a column 
of mercury, 2 inches of mercury equalling one pound pressure per 
square inch; thus, 20 inches of mercury means 10 lbs. pressure 
per square inch. If the steam-gauge shows 10 lbs. pressure, and 
the vacuum-gauge registers 20 inches, there is a vacuum equal to 
10 lbs. per square inch in the condenser. 

The vacuum is maintained in the condenser by the exhaust 
steam being constantly condensed, by either mixing with the cold 
injection-water or by being brought in contact with the cooling 
surface of the tubes in the surface condenser. 

A vacuum is produced in a condenser by the steam (when it first 
enters) driving out the air; and, when condensed into water, it oc¬ 
cupies 1669 times less space than it did before being condensed, 
as 1700 cubic feet of steam produce one cubic foot of water. 

To produce a vacuum in a jet condenser, open the blow-through 
valve, when the steam, in its passage through, will blow out all 
air and water in the condenser; and as soon as the steam issues 
from the snifting-valve the blow-through valve may be shut, and 
the injection-cocks opened, when the cold water mixing with the 
steam forms a vacuum. AVhen the gauge shows a sufficient vac- 


THE ENGINEER^ HANDY-BOOK. 


851 


uum, shut the injection-cocks, in order to prevent the condenser 
from being flooded. 

To produce a vacuum in a surface condenser, open the injection- 
valve shortly before starting the engine, so that the circulating- 
water may enter the condenser tubes, and cool them. Then, when • 
the engine is started, the exhaust steam comes in contact with the 
cooling surface of the tubes, and is condensed when a vacuum is 
formed. 

If the steam-gauge shows 60 lbs. pressure, and the vacuum- 
gauge 26 inches, it means that there are 60 lbs. of steam pressing 
on one side of the piston, and 13 lbs. of resistance removed from 
the other side. 

The state of the vacuum is shown by the vacuum-gauge attached 
to the condenser; and, if it be imperfect, the cause must be ascer¬ 
tained and the fault corrected. If the water in the hot well be 
above the ordinary temperature, more injection-water must be ad¬ 
mitted ; and, if the vacuum continues imperfect, the cause may be 
due to an air-leak, the location of which the engineer must 
endeavor to discover. Very often the fault will be found in the 
valve- or cylinder-cover, which must then be screwed down more 
firmly; or in the joint of the eduction-pipe, the gland of which 
will require to be tightened. The door of the condenser should 
also be examined. The joints of the condenser may be tested by 
holding a candle to them, the flame of which will be drawn in if 
the joints are leaky. 

A vacuum is not power, as all power in the steam-engine is de¬ 
rived from the pressure of the steam on the piston; if there is no 
resistance on one side of the piston, the entire pressure on the 
other side is available. Whenever there is resistance on one side 
of the piston, it must be deducted from the pressure on the other 
side. There is hardly such a thing as a perfect vacuum. The 
philosopher Torricelli asserted correctly that nature abhors a 
vacuum ; consequently, if a perfect vacuum can be attained, it can¬ 
not be maintained long, as the wear of the machinery, the packing 
around the air-pump rod, and other causes, contribute to impair it. 


352 


THE engineer’s HANDY- BOOK 






























































































































































































































































tiie engineer’s handy-book. 


353 


Air-Pumps. 

All condensing engines have of necessity to be provided with 
an air-pump, for the purpose of extracting the air, injection- 
water, and the water of condensation from 
the condenser, in order to maintain a vac¬ 
uum. There does not appear to he any 
uniform, recognized rule, among marine 
engineers or manufacturers of surface-con¬ 
densing compound engines, for proportion¬ 
ing the air-pumps to the steam-cylinder, as, 
while some builders make the capacity of 
their air-pumps one-eighth of that of the 
low-pressure cylinder, others make it one- 
tenth, and others one-eleventh ; the average 
of the number examined being about oue- 
ninli. 

The air-pumps of the steamships Penn¬ 
sylvania, Ohio, Indiana, and Illinois, of the 
American Line, are one-eleventh the capac¬ 
ity of the low-pressure cylinder. And, as 
these engines have the reputation of being 

very economical, it should be presumed s ., oll( , n „ f! , Marin.* Airt 
that their proportions are good ; neverthe- Pump, 

less, they are evidently too large, as one-fifteenth would be nearer 
to a correct proportion. The tendency among marine engineers is 
to overdo the thing in the case of air-pumps, perhaps under the im¬ 
pression that a large air-pump creates a better vacuum, and, as a 
result, air-pumps of enormous diameter and long stroke are at¬ 
tached to marine engines; whereas, the air-pump has very little to 
do with the vacuum, its functions being simply to clear the con¬ 
denser of water and air. Any proportion that will accomplish this 
will fulfil all the necessary requirements. An air-pump too large 
for the purpose for which it is intended, can have no other effect 
than to absorb much of the power which might be utilized in in- 



30* 


X 














































354 


TIIE ENGINEER’S HANDY-BOOK. 

creasing the speed of the engine and economizing the fuel. The air- 
pump piston, being resisted by the pressure of the atmosphere, ab¬ 
sorbs from four to five per cent, of the power of ordinary simple con¬ 
densing engines, and from two to three per cent, in the better class 
of compound marine engines ; the power required to work it being 
greatest when the vacuum is most perfect, and least when the 
vacuum is impaired. A good deal also depends on the mechanical 
arrangement employed to work it, as well as on the condition of 
its packings, bearings, proportions, etc. 

The capacity of the air-pumps of condensing engines using a 
jet or spray, ranges from one-fifteenth to one-twentieth the capac¬ 
ity of the cylinder. As it requires from 22 to 30 times as much 
water to condense steam as there is water in it (according to the 
pressure and temperature), the air-pumps ought to be proportioned 
to meet the maximum demands. The right proportions of air- 
pumps for both jet- and surface-condensing engines may be found 
by calculating the displacement of the steam-piston, and that of 
the air-pump for one minute, and dividing the former by the 
latter. The use of the air-pump in connection with condensing 
engines, as before stated, is not an absolute necessity in all cases, 
as, with a head of water having a fall of about 13 feet, a vacuum 
can be formed and maintained in the condenser without an air- 
pump, providing the end of the delivery-pipe is submerged in a 
tank of water. 

Vertical air-pumps, with valves in their pistons or buckets, give 
the best satisfaction, as, in that case, the air and vapor are lifted 
and forced out of the condenser, relieving the exhaust and in¬ 
creasing the vacuum. The capacity of the openings through the 
valve-seats of air-pumps should be such that the maximum flow 
of the water through them will not exceed 10 feet per second. 
For instance, suppose a pump of 12 ins. stroke to make 50 strokes 
per minute, the maximum travel of the bucket at midstroke will 
be about 2*6 feet per second. Then, as 10 2‘6 — 3*84, the capac¬ 

ity of the opening should not be less than one-fourth the area of 
the pumps. 


THE ENGINEER’S HANDY-BOOK. 


355 


Air-pumps are frequently very injudiciously located, being 
placed above the condenser; whereas, if placed below it, their re¬ 
quirements would be fewer, as the water would fall by gravity 
from the condenser into the air-pump. In some cases the air- 
pump extends down through the condenser, so that the openings 
are nearly on a level with the bottom of the condenser, which is 
a good arrangement in every respect, except that it necessitates a 
long stroke, which has a tendency to absorb power. 

Independent air-pumps, a cut of which may be seen on page 
352, having an air-cylinder at one end, the circulating-water cyl¬ 
inder at the other, and the steam-cylinder in the middle, are being 
very generally adopted on ocean steamers. The claim set up for 
them is, that, as they are independent of the engine, they can be 
worked faster or slower, according to the circumstances of the 
case; that they absorb none of the power of the engine, and are 
freer from liability to accident in stormy weather, or whenever the 
engine races, than air-pumps attached to the main engine; that 
they can be started, and a vacuum formed, before the engine com¬ 
mences to work; that the injection-water can be more easily reg¬ 
ulated ; that they require no expensive foundation; that, in con¬ 
sequence of the water- and air-pistons being on each end of the 
steam-piston, they have a more steady and uniform motion than 
the ordinary air-pump has, and that, in consequence of all their 
parts being accessible, they can be easily examined, and any de¬ 
rangement remedied or readjusted, without interfering with the 
working of the engine. 

In a surface-condensing engine, the air-pump has only to ex¬ 
tract the water resulting from the condensed steam and the uncon- 
densed vapor from the condenser. In a jet-condensing engine, 
the air-pump has to withdraw both the injection-water and the 
water of condensation; the work to be performed by the latter 
being from 25 to 30 times greater than that of the former. 

An air-valve is sometimes fitted to a circulating, reciprocating, 
or double-acting pump, for the purpose of admitting air to the 


356 


THE ENGINEER’S HANDY-BOOK. 


water on the up stroke. As the valve is closed against the down 
stroke, the air admitted serves to soften the shock of the water. 

A bucket air-pump is a single-acting pump, being, in fact, a 
piston with a valve fitted to it, which closes on the up stroke and 
opens on the down, lifting a quantity of water equal to its capacity 
at each stroke of the engine. 

A piston air-pump is a double-acting pump, the piston being 
solid. It is fitted with suction- and delivery-valves, and dis¬ 
charges with each stroke. 

A plunger air-pump is a double-acting pump, resembling the 
bucket air-pump, except that it has no head-valves, and that the 
bucket-rod is fitted with a plunger. The effect of this is, that the 
plunger, owing to its displacement, discharges on both the up and 
the down stroke. 

The double-acting air-pump has both suction- and delivery- 
valves ; but it is possible with the single-acting pump, in some 
cases, to dispense with either the one or the other. They are 
generally made with pistons, though sometimes with plungers. 

An air-pump with a foot-valve and no discharge-valve would 
be most affected by a leaky stuffing-box; and, while the foot-valve 
remains, the pump will draw water, but if removed, it will fail to 
work. 

An air-pump trunk is a hollow cylinder attached to the bucket 
or piston, and working through a stuffing-box. Such an arrange¬ 
ment is rendered necessary when the pump is worked directly off 
the crank-shaft, or where it is located so close to the levers, 
through which the motion is transmitted from the engine, as to 
render the appliance of an intervening cross-head and links im¬ 
possible. The difference in the discharge is equal to the relative 
difference between the displacement caused by an ordinary air- 
pump rod and that caused by the trunk. 


THE ENGINEER’S HANDY-BOOK. 


357 


The air-pump pet cock or valve is generally placed below the 
head-valve and above the bucket. It opens with the down stroke 
of the pump, and admits air to act as a cushion on the water. 
When the delivery-valve is opened, the engineer can tell by its 
action whether the pump is working properly or not. 

An air-pump bucket is a hollow piston, generally made of brass, 
with a grating in the top, and a boss (water-tight) which receives 
the rod in its centre, from which strengthening ribs run to the rim 
of the bucket. The outside of the bucket is grooved to receive 
water-tight packing. The valves, which are generally of India- 
rubber, and whose lift is regulated by a guard secured by a nut, 
and against which the valve is pressed when the bucket is on the 
down stroke, are on the top of the grating. 

Air-pump rods are generally made of wrought-iron, and covered 
with a skin of Muntz metal, or brass, to prevent the oxidization to 
which wrought- or cast-iron rods are exposed. 

A ship’s side air-pump discharge-valve is generally a mitred 
valve, with its spindle passing through a gland in the cover, on 
which a weight is placed to keep it shut. It differs from a stop- 
valve in having a lift and weight. 

There are numerous contrivances in use for dispensing with 
the air-pump, such as the injector condenser, which produces a 
sheet of water in the exhaust-pipe; but the necessary arrangements 
for operating them generally cost more than a good reliable air- 
pump, though the first cost of the former is less than that of the 
latter. Besides, the vacuum is never so perfect when produced by 
any such arrangement as when created by a close condenser and 
air-pump. This becomes obvious, since we know that, even with 
the most perfect mechanism, it is almost impossible to attain a 
perfect vacuum, and maintain it for any length of time, as nature 
abhors a vacuum, as the atmosphere on the outside of a. vessel 
is constantly endeavoring to equalize any unbalanced pressure 
that may exist on the inside. 


358 


THE ENGINEER’S HANDY-ROOK. 



I 

S3 

cj £3 

Oi'O 

H A 

O 

r* 

in 

C Q) 

O uM 
r-< 0^ O 

Capacity per 

Minute, 

i 

0 a5 

P a> 

C2 Q< 

1 

c . 

o ^ 

•g Ph 

o-- 


h 

'S 

at Ordinary 

Speed. 


xr 



"o 

CO 

O CO 





H 

2 r-i 

a? 

12 

6 

12 

2*61 

100 strokes, 

261 gal. 

n 

21 

5 

14 

9 

12 

3*30 

100 

4 ; 

330 “ 

9 

3 

5 

14 

10 

12 

4*08 

100 

u 

408 “ 

9 

3 

5 

10 

9 

18 

4*96 

70 

u 

347 “ 

H 

2 

6 

12 

10 

18 

6-12 

70 

u 

428 “ 

n 

24 

8 

14 

12 

18 

8-80 

70 

u 

616 “ 

2 

3 

8 

145 

12 

21 

11-75 

50 

u 

588 “ 

2 

3 

0 

14! 

10 

36 

12-24 

35 

a 

428 “ 

9 

3 

8 1 


. co co co Discharge 
i pipe. 


































































































































































































359 


THE ENGINEER'S HANDY-BOOK 



Marine Wrecking-Pump. 


Steam- 

Cylinder. 

Water- 

Cylinder. 

Stroke. 

Gallons 

per 

Stroke. 

Capacity per Minute, 
at Ordinary Speed. 

Steam- 

Pipe. 

Exhaust- 

Pipe. 

Suction- 

Pipe. 

Discharge 

Pipe. 

6 

3f 

7 

•33 

125 strokes, 42 gal. 

3 

4 

1 

2 

14 

i r 


10 

•69 

100 “ 

69 

1 

14 

91 

2 

7^ 

7 

10 

1-66 

100 “ 

166 “ 

1 

14 

4 

3 

8 

5 

12 

1-02 

100 “ 

102 “ 

1 

n 

34 

3 

8 

8 

12 

2*61 

100 “ 

261 “ 

1 

14 

5 

34 

10 

6 

12 

1-47 

100 “ 

147 “ 

n 

9 

34 

0 

O 

10 

_ 

10 

12 

4*08 

100 

408 «* 

n 

9 

5 

O 1 
Of 































































































































































































































































































360 


THE ENGINEER’S HANDY-BOOK. 


The Salinometer.* 


A Salinometer is a form of hydrometer used to determine the 
quantity of salt contained in the water of marine boilers, and by 

which the amount of water necessary 
to be blown out, to keep the water in 
the boilers at a certain density, may be 
ascertained. It is a graduated glass 
tube, and floats in the water at a height 
proportional to its density or saltness. 
It is marked 0 for fresh water; for 
sea-water that contains 1 lb. of salt to 
32 lbs. of water; ^ when it contains 
2 lbs. of salt to 32 lbs. of water, and so 
on. Each division is subdivided into 
four parts, showing halves and quarters. 
It is graduated for a temperature of 
200° Fah. A uniform standard of 
temperature is necessary, since water 
must be taken from the pressure in the 
boiler, in order that it may assume its 
regular temperature under the pressure 
of the atmosphere, because steam of 
different pressures has different tem¬ 
peratures, and a difference in tempera¬ 
ture will alter the indications of the 
hydrometer. 

The amount of salt in the water of 
a boiler may be ascertained by observ¬ 
ing the degree of the boiling-point by 
means of a thermometer. To do this, 
a sufficient quantity of the water in the boiler should be drawn 
off in a long copper vessel, and brought to the boiling-point. Then 
immerse the thermometer. For every pound of salt contained in 
32 lbs. of water, the temperature rises one degree. Thus, if the 



The Salinometer. 


* See page 651. 






























































































THE ENGINEER’S HANDY-BOOK. 


361 


water contains ^ of salt, it will boil at 213°; if A, at 214°; if 
at 215*5°, and £f> at 216*6°. 

Salt-water, at the usual density, contains 3 ^ of its weight of salt; 
consequently, if one pound of salt enters the boiler with every 32 lbs. 
of water, and 16 lbs. of that water be evaporated, the one pound of 
salt remains in the proportion of 1:16. Again, if i of the 16 lbs. of 
water remains to be evaporated, the one pound remains in the 8 lbs. 
of water. Now, if these 8 lbs. of water were blown out of the boiler, 
the salt would go with it; and so long as that proportion is carried out, 
the saturation cannot exceed ^; from which it is clear that, to keep 
water at %%, one-fourth must be blown out; one-third at g 3 2 , and at 
3 2 2 one-half of the water used for feed must be blown out. 

The errors in the hydrometer may be corrected in the following 
manner: Every 10° difference in temperature will vary the indi¬ 
cations g of gtj, 200° Fall, being the standard. Then, if the water 
be 10° over 200° Fall., it will show ^ of ^ less than its true density ; 
and if 10° below 200° Fah., it will indicate ^ of 3 I? more. Moreover, 
if the grade be 200° Fall., the thermometer shows 210°, and the hy¬ 
drometer indicates a density of 3 ^, the true density will be 2 ^-; 
and if the temperature be 190 3 , it will be 1J. 

A Salinometer may be constructed by taking a long glass tube, 
and inserting in it sufficient shot to sink it in fresh water, marking 
the point at which the water stands in the tube. Then immerse 
the tube in water containing ^ part of salt, when the point at 
which the water stands will be the sea-water mark. Similarly 
immerse in water containing etc., up to of its weight 

of salt, marking off the respective points at which the water stands. 
Transfer these marks to a scale, and paste it inside the bottle in 
exactly the same position as the marks on the bottle, and the result 
is a good salt-gauge. The temperature must always be the same 
as when the hydrometer was graduated. 

How to use a Salinometer. — Draw off some water from the 
boilers, and when the ebullition has ceased, try its temperature with 
a thermometer. If the temperature exceeds that marked on the 
salinometer, let it cool till it reaches that degree; and if the tem- 
31 


362 


THE ENGINEER’S HANDY-BOOK. 


perature is less than that marked on the salinometer, it must be 
raised till it reaches that degree. Then immerse the salinometer 
in the water and let it float; if the level of the water is at or 
less, there is no occasion for blowing off; but if it exceeds -g 2 ^, the 
water must be changed. The degrees of temperature usually 
marked on the salinometer are 190°, 200°, 210°. Before using the 
salinometer, it should be wet all over with water. 

TABLE 


SHOWING THE PROPORTION OF SALT IN THE WATER OF DIFFERENT SEAS, 



PARTS IN 1000. 

Baltic Sea. 

6*60 = yL 

Black Sea. 

21-60= ¥ V 

Arctic Sea. 

28-30= 

1 risli Sea,. 

33-76— A 

British Channel. 

35*50= ig 

■ 


Mediterranean Sea.... 
Atlantic at Equator... 

South Atlantic. 

North Atlantic. 

Dead Sea. 


PARTS tn 1000. 


39-40 = A- 
39*42 = X 
■41*20 = & 
42-60 = 
385-00 = U 


TABLE 


SHOWING THE BOILTNG-POINT OF SALT-WATER AT THE DIFFERENT DE¬ 
GREES OF DENSITY, WHEN THE BAROMETER STANDS AT 30 INCHES. 



SATURATION. 

BOILING- 

POINT. 

F resh water. 


212 ° 

Fah 

Sea-water. 

1 

3 2 

213-2 

U 

<< 

2 

32 

214-4 

u 

U 

3 

3 2 

215-5 

u 

U 

4 

3 2 

216-7 

u 

a 

5 

3 2 

217-9 

u 

u 

6 

3 2 

219-1 

u 

« 

7 

3 2 

220-3 

u 

a 

8 

3 2 

221-5 

i( < 

« 

9 

3 2 

222.7 

u 

« 

1 0 

3 2 

223-8 . 

u 

a 

1 1 

3 2 

225*0 

u 

u 

1 2 

3 2 

226*1 

u 


The meaning of the term saturation, in its relation to the water 
of marine boilers, means the quantity of salt it contains per gallon. 







































363 


THE ENGINEER’S HANDY-BOOK. 

Saturation at ^ means 4 oz. salt to one gallon fresh water; 
3^7, 8 oz. salt to one gallon water; 3^, 12 oz. salt to one gallon 
water, and so on. In carrying the water at -£>, twice as much is 

converted into steam as is blown off. At 3^, the water blown off 

1,3 

and that converted into steam are equal. At ii_ the water con- 

32 * 

verted into steam equals | of the water blown oft*. 

The following table shows the method of regulating the satura¬ 
tion. 600 gallons of water, which is supposed to contain 7200 oz. 
of salt, being made the basis of the calculation. 


Blown out . 


Fed in at 3I7 to make 
up for deficiency 


Fed in 


Fed in 


Water 

in 

Gallons. 

Salt 

in 

Ounces. 

600 

200 

7200 

2400 

400 

200 

4800 

800 

600 

200 

5600 

steam 

400 

200 

5600 

800 

600 

200 

6400 

steam 

400 

200 

6400 

800 

600 

7200 


4 evaporated. 


I evaporated. 


The following calculation shows the loss induced by blowing 
off’ as well as the gain derived from fresh-water condensers, pro- 

























364 


THE ENGINEER’S HANDY-BOOK. 

viding they are tight, and the condensation of the steam be per¬ 
fect. The degrees of heat imparted to the water converted into 
steam are the total heat of the steam minus the degrees of heat 
in the feed-water. The heat lost by blowing off is the difference 
between the heat of the feed-water and the sensible heat of the 
steam. 

Rule for finding the percentage of loss induced by blowing off 
to prevent saturation. 

Multiply loss by blowing off by 100, and divide the product by 
the total degrees of heat imparted to the water plus the heat lost 
by blowing off. (Observe that for 3 ^, as twice as much water is 
converted into steam as is blown off. For the amount is equal. 

For _i+, the amount is f, and so on.) The result is the percentage 

of loss. 

Example.— 3^. 

Feed-water, 110° ; total heat, 1193*45° ; sensible steam, 260°. 

260° — 110° — 150° heat lost by blowing off. 

1193-45° — 110° = 1083-45° total heat. 

1083*45° x 2 = 2166*9° + 150° = 2316*9° total heat imparted, 
and loss by blowing off*. 

(150° x 100) -r- 2316*9° = 6*47 per cent, of heat lost by blow¬ 
ing off. 

The Barometer. 

The Barometer is an instrument used for observing the press¬ 
ure and elasticity, or variations in density, of the atmosphere. 
Its essential part is a well formed glass tube, closed at one end, 
perfectly clear and free from flaws, 33 or 34 inches long, of equal 
bore, filled with pure mercury, and inverted; the open end being 
inserted in a cup partly filled with the same metal, so that the 
mercury in the tube may be supported by atmospheric pressure. 

When the air is dry and light, the mercury in the barometer 
rises; when the air is humid and heavy, it falls. When changes 
in the weight of the atmosphere take place gradually, they are 


THE ENGINEER’S HANDY-BOOK. 365 

imperceptible to human sensation; and if it were not for this instru¬ 
ment, it would be impossible to estimate accurately atmospheric 
conditions. If, in fine, clear weather, a rain-storm is approach¬ 
ing, the increasing humidity of the atmosphere will be noted by 
the fall of the barometer long before it will be perceived by ordi¬ 
nary observers. Hence, the condition of the barometer is an indi¬ 
cation of not only the weather at the time, but of that which is 
to follow during the course of several hours. It is in a constant 
state of variation, governed by the condition of the air. The mer¬ 
cury in the barometer stops falling at 30 inches at sea-level. 


TABLE 

SHOWING THE WEIGHT OF THE ATMOSPHERE PER SQUARE INCH CORRE¬ 
SPONDING WITH DIFFERENT HEIGHTS OF THE BAROMETER. 


Barometer 

in 

Inches. 

Atmosphere 

in 

Pounds. 

Barometer 

in 

Inches. 

Atmosphere 

in 

Pounds. 

Barometer 

in 

Inches. 

Atmosphere 

in 

Pouuds. 

28-0 

13-72 

29-1 

14-26 

30-1 

14-75 

28T 

13-77 

29-2 

14-31 

30-2 

14-80 

28-2 

13-82 

29-3 

14-36 

30-3 

14-85 

28-3 

13-87 

29-4 

14-41 

30-4 

14-90 

28*4 

13-92 

29-5 

14-46 

30-5 

14-95 

28-5 

1397 

29-6 

14-51 

30-6 

15-00 

28-6 

14-02 

29-7 

14-56 

30-7 

1505 

28*7 

14-07 

29-8 

14-61 

30-8 

15-10 

28 8 

14-12 

29-9 

14-66 

30-9 

1515 

28*9 

290 

1417 

14-21 

30-0 

14-70 

31- 

15-19 


Thermometers. 

The Thermometer is an instrument for measuring variations of 
heat or temperature. It consists of a bulb and glass stem of uni¬ 
form bore. A sufficient quantity of mercury having been intro¬ 
duced, it is boiled, to expel the air and moisture, and the tube 
is then hermetically sealed. The properties of mercury which 
render it preferable to all other liquids are these: it supports, 
31* 



















366 


THK ENGINEER’S HANDY-BOOK. 


before it boils, more heat than any other fluid, and endures a 
greater cold than would congeal most other liquids. 

The standard points are ascertained by immers¬ 
ing the thermometer in melted ice and in the steam 
of water boiling under the pressure of 14'71bs. on the 
square inch, and marking the positions of 
the top of the column. The interval Vt J 
between those points is divided into the VjjJI 
proper number of degrees,— 100 for the T 
Centigrade scale, 180 for Fahrenheit’s, ili 
and 80 for Reaumur’s. :|i 

The word “zero” is of Arabic origin, 
and means empty; hence nothing. Ab- ]j|{ 
solute zero is a temperature which is fixed jh 
by reasoning, although no opportunity ;ji| 
ever occurs for observing it. It is the 
temperature corresponding to the disap- 
pearance of gaseous elasticity; or, in Ji 
other words, the point where gas would lb I 
become a solid, as where water becomes jjd|A 
ice. This temperature is called zero in 11 jll 

The Hot-well reference to all the gases, and the The Uptake 
Thermometer. . . * . Thermometer, 

positions ot the absolute zero on the 

ordinary scales would be 

Reaumur’s scale ..... 219*2 below 0° 

Centigrade * . . . . . . 244 “ 

Fahrenheit ...... 46T22 “ 

Rules for Comparing Degrees of Temperature Indicated by Dif¬ 
ferent Thermometers. 1. Multiply degrees of Centigrade by 9 and 
divide by 5; or multiply degrees of Reaumur by 9 and divide by 4. 
Add 32 to the quotient in either case, and the sum is degrees Fah¬ 
renheit. 2. From degrees of Fahrenheit subtract 32; multiply the 
remainder by 5, and divide by 9 for degrees Centigrade; or mul¬ 
tiply by 4, and divide by 9 for degrees Reaumur. The abbrevia¬ 
tion for Fahrenheit is “ Fah.” ; tor degree, °. 



























the engineer’s handy-book. 


367 



Marine Steam-Engine Register. 

This instrument is designed for application to marine steam- 
engines. It consists of a circular box faced with a dial, in which 
are cut, side by side, 
six or more slots, 
through which may 
beseen the numbers 
representing the 
revolutions of the 
engine. This dial 
is called the “coun¬ 
ter ” or “ register,” 
which is worked 
by an attachment 
to any suitable part 
of the engine, from 
which a vibratory 
n.iotion may be 
communicated to 
an arm attached to 
a central horizontal 
shaft placed paral¬ 
lel to the dial, into 
the ends of which 


is fixed a frame carrying a small shaft, parallel to the former, to 
which six arms are attached in such a way that the right arm may 
fall without the others, but cannot rise without carrying all the rest. 

This framework, with the pall-shaft, etc., by the motion of 
the arm attached to the engine, describes an arc of 36°, or 
of a circle. The ends of the palls, respectively, rest on and 
slide over 6 cylinders placed side by side on the central shaft, all 
of which move in the same direction, and are numbered from 
right to left. On the right-hand edge of each cylinder are cut 
10 slots, and on the left hand only one slot, which are of such a 
















368 


THE ENGINEER^ HANDY-BOOK. 


size as to admit the end of one of the palls. Then, on the back 
motion of the framework, etc., the pall is carried back until it 
drops in, when the forward motion carries with it the cylinder so 
locked. 

In the spaces between the laps, in each cylinder, and opposite 
to one of the slots in the dial face, the numbers 1, 2, 3, etc., 
to 0, are engraved at equal distances around the circumference. 
The palls are placed one over each of the slots, so that the 
pall can fall into the inner cylinder only when the slot in the 
outer one comes directly under it. As this occurs only once 
in a whole revolution, and as the motion of the palls is only 
through one-tenth of a circle, it follows that cylinder No. 2 can 
only be moved through one-tenth of its circumference after cyl¬ 
inder No. 1 has moved a whole revolution, or ten times that space, 
and so on. Thus, if the figures on No. 1 represent units, those on 
No. 2 will be tens, on No. 3, hundreds, etc. It will be observed 
that every revolution of the engine insures one-tenth of cylinder 
No. 1 to move round, inasmuch as the ten slots in its right-hand 
edge are not covered by any other cylinder, as is the case with 
the others. 

Rule for Finding Ike Number of Revolutions the Engine has 
made during the Voyage. 

Subtract the number at which the counter stood at the beginning 
of the voyage from that which is indicated at the end of it; the re¬ 
mainder will be the number of revolutions made during the voyage. 

To Reduce the Time the Counter has been Working into Minutes. 

Multiply the days by 24,* the product will be the hours; multi¬ 
ply this by 60,f the result will be the minutes during which the 
counter has been working, or divide the number of revolutions by 
the minutes the counter has been working ; the quotient will be the 
average number of revolutions made by the engine per minute. 


* 24 hours being equal to one day. 


f As 60 minutes = 1 hour. 




THE ENGINEER’S HANDY-BOOK. 


369 


Spring-, Mercury-, Syphon-, and Vacuum-Gauges.* 

Figure I shows an inside view of the Lane spring steam- 
gauge. As may be observed, it consists of a hollow brass tube, 
a lever, connecting- 
link, sector, pinion, 
and pointer. Its oper¬ 
ation is as follows: 

Pressure is exerted 
in the tubes, A, A, 
through the nipple, B, 
the effect of which 
is to elongate or 
straighten it. Tlie 
consequence is, that 
the link, C, draws the 
lever, E, and the sec¬ 
tor, F, which moves 
the pinion, which is 
not shown, but which 
carries the pointer, G. 

The higher the pressure, the more the tubes will be expanded or 
elongated, and the higher the pointer will be carried up. As the 
pressure decreases, the tubes have a tendency to contract, and the 
pointer again assumes its natural position at zero. 

Fig. 2 (page 370) represents the Bourdon spring steam-gauge. 
It consists, as in the case of the Lane, of a hollow metal tube, con¬ 
necting-link, sector, pinion, coil-spring, and hand or pointer. As 
will be seen, though the mechanism is reversed, the principle is 
the same as in the Lane gauge. The pressure exerted in the 
hollow tube, G, has a tendency to expand or elongate it; the result 
of which is, that the link, H , draws the sector, J, (which swings on 
the stud I) to the right, the upper end of which turns the pinion, 
K, which carries the pointer to the right also. A coil-spring is 

* See page 658. 

Y 

















370 


THE ENGINEER’S HANDY-BOOK. 


attached to the stud, "which carries the pointer to assist in bring¬ 
ing it back to a state of rest, as the pressure decreases. 

The advantages of spring-gauges are, that they are light, cheap, 
and simple, and are not affected by jar or jolting; their disad¬ 
vantages are, liability to corrode, and the spring losing its ten¬ 
sion ; they require to be tested and corrected at least once a year. 
When steam-gauges of any kind are set up, the end of the pipe 
next the gauge should invariably be filled with cold water. The 
steam should never be allowed to act directly on a steam-gauge 

when located in cold 
situations, where they 
are liable to freeze. 
The valve on the boil¬ 
er should be closed, 
and the drip attached 
to the gauge opened, 
in order to allow the 
water to ru n out. The 
drip on the gauge 
should be closed be¬ 
fore the steam is 
turned in from the 
boiler, in order that 
sufficient steam may 
be condensed in the 
pipe to furnish the 
quantity of water necessary to keep the steam from striking the 
gauge. 

The spring-gauge can also be used as a vacuum-gauge, by re¬ 
versing the application of the pressure, which has a contrary effect 
on the tube. For instance, as exhaustion takes place in the tube, 
its power of resisting the pressure of the surrounding atmosphere, 
which acts upon it, varies also, and it consequently again coils under 
that pressure in regular ratio with its variation, and indicates the 
degree of vacuum in the condenser. 



















































































































THE ENGINEER’S HANDY-BOOK. 371 

A siphon-gauge is a bent tube, inverted, and partially filled 
with mercury. The orifice of the short leg is connected with the 
boiler, and the long leg is open to the atmosphere. The steam 
pressing upon the mercury in the short leg with greater force 
than the pressure of the atmosphere, causes the mercury in the 
other leg to rise, and indicates the excess of pressure above the 
atmosphere. To the amount shown by the gauge must be added 
the pressure of the at¬ 
mosphere. Thus, if a 
siphon-gauge shows 
15 lbs. pressure, the 
boiler-pressure is 30 
lbs. 

A mercurial gauge, 

for high - pressure 
steam - engines, con¬ 
sists of a glass tube 
open at the lower 
end, and closed at the 
top, containing air in 
its ordinary state. Its 
lower end is placed 
in a cistern of mer¬ 
cury. When the cock 

is opened, the steam 

,, , f. Fig 1 . 3.—The Spring Steam-Gauge, 

passes through, forc¬ 
ing the mercury up the glass tube, thereby compressing the air 
in the tube above the mercury. When the air is compressed to 
one-half its original space, the pressure is doubled; to one-third, 
it is trebled ; to one-fourth, it is quadrupled, etc. 

A barometer-gauge is a tube of glass, more than 30 inches long, 
closed at one end, and filled with mercury, then inverted so that 
the lower or open end will be immersed in a cistern of mercury, 
when the mercury in the tube will sink, rising in the basin until 
its weight balances the pressure of the atmosphere, which, by its 











372 


THE ENGINEER'S HANDY-BOOK. 


elasticity, is endeavoring to force the mercury up the tube. The 
mercury in the tube will be found to stand about 30 inches higher 
than the level in the basin, varying siightly, according to the state 
of the atmosphere. 

The scale of a barometer-gauge may be explained as follows: 
As 30 inches of mercury press down with the same force as the 
atmosphere, say 15 lbs. per square inch, two inches of mercury 
correspond to one pound of pressure, and a scale of inches meas¬ 
ured from the mercury in the cup upwards must be fixed near 
the glass tube. As the vacuum, while the engine is working, may 
be supposed to be good, the scale need only be marked to a few 
inches below 30 inches, every fall of two denoting one pound of 
pressure in the condenser. 

The sources of error, in estimating the vacuum by this gauge, 
arise from the following two facts: That the pressure of the at¬ 
mosphere, or the mercury in the cup, is liable to change. That 
the gradations on the scale are marked, on the supposition that 
the level of the mercury is stationary; because it is from this 
level that the scale commences. Therefore a fixed scale must be 
erroneous, on account of the sinking of the mercury in the cup 
as it rises in the tube. 

The first source of error may be corrected by observing the 
actual height of a weather barometer, and subtracting it from the 
height as shown by the gauge. This will be correct, if a tube of 
a standard diameter is used. This error may be corrected by a 
short gauge, similar to what a weather barometer would be if it 
were enclosed in a space, communicating with the condenser. In that 
event, before a vacuum is created, the mercury would stand as 
high in the glass tube as in the weather barometer. On creating 
a vacuum, thus taking off the pressure from the mercury in the 
cistern, the mercury would fall in the tube. In this instrument, 
the less the height of the mercury the better the vacuum. 

The second source of error may be obviated by having a mov¬ 
able instead of a fixed scale, so that its lower end might always 
be kept in contact with the surface of the mercury in the cup. 


THE ENGINEER^ HANDY-BOOK. 


373 


A siphon-gauge, such as has been spoken of, may be used as a 
vacuum-gauge. When so used, it is necessary to connect the long 
leg with the condenser, placing a stick in the short leg. In this 
case the scale would require to be graduated directly contrary 
to that for steam. The state of the atmosphere will affect the 
gauge. The pressure in the steam-boiler may be ascertained by 
the temperature, by the safety-valve, or by the steam-gauge. 

The Mariner’s Compass. 

The object of the mariner’s compass is to enable travellers to 
steer their course with certainty from one location to another. 
The needle is understood to point to the north, and the other 
points, east, west, etc., are easily found. In certain parts of the 
world, however, the needle does not point to the north, but is drawn 
to the right or left of true north. This is called the variation of the 
compass, and must be known accurately by the navigator, in order 
to correct and steer the right course. For instance, in crossing 
the Atlantic Ocean, the variation of the compass amounts in sail¬ 
ing vessels to 2i or 2f points westerly, and the course steered must 
be corrected accordingly. If a due east course is desired, the 
vessel must be steered 21 or 2f points south. 

Off the Cape of Good Hope, the variation of the compass in 
ships bound to India or Australia is 2| points easterly, and, in 
order to make a due east course, it is necessary to steer 2f to the 
north, or left of her course; while towards the equator there is 
hardly any perceptible variation of the compass at all. The best 
means of finding out how much the compass varies in different 
parts of the world is by observations of the sun taken with the 
compass, and the difference between the true and magnetic compass 
is the variation, which must be applied as a correction to the course, 
steered. In iron ships or steamers, the deviation must be considered 
as well as the variation. This is due to the local attraction caused 
by the iron, and must be carefully understood before steamers or 
iron ships go to sea. Before a vessel proceeds on her first voyage, 
the compass must be carefully swung and magnets fixed to the 
deck. 


32 


374 


THE ENGINEER’S HANDY-BOOK. 


TABLE 

OF RHUMBS, OR POINTS OF THE COMPASS. 


Points. 

Angles. 

NORTH. 

NORTH. 

SOUTH. 

SOUTH. 

* 

O 

2 

48 

45 

N i E 

N 4 W 

S 4 E 

S 1 W 

2 

5 

37 

30 

N 2 E 

N 2 W 

S 1 E 

S 2 w 

A 

4 

8 

26 

15 

N f E 

N f W 

S f E 

s t w 

1 

11 

15 

0 

n by e 

n by w 

s by e 

s by w 

a 

14 

3 

45 

n by e t e 

n by w t w 

s by e t e 

s by w 1 w 

a 

16 

52 

30 

n by e I e 

n by w 2 w 

s by e 2 e 

s by w 2 w 

it 

19 

41 

15 

n by e f e 

n by w t w 

s by e f e 

s by w t w 

2 

22 

30 

0 

NNE 

NNW 

SSE 

SSW 

21 

25 

18 

45 

NNE 4 E 

NNW 1 W 

SSE 4 E 

SSW 4 W 

2k 

28 

7 

30 

NNE 1 E 

NNW 2 W 

SSE 2 E 

SSW 2 w 

21 

30 

56 

15 

NNE f E 

NNW t W 

SSE t E 

SSW 4 w 

3 

33 

45 

0 

ne by N 

NW by N 

se by s 

sw by s 

31 

36 

33 

45 

NE f N 

NW f N 

se| s 

sw f s 

31 

39 

22 

30 

NE 2 N 

NW 1 N 

SE 2 S 

SW 2 s 

31 

42 

11 

15 

NE t N 

NW 4 N 

SE | S 

sw 1 s 

4 

45 

0 

0 

NE 

NW 

SE 

sw 

41 

47 

48 

45 

NE t E 

NW 1 W 

SE 1 E 

SW 4 w 

41 

50 

37 

30 

NE 2 E 

NW 2 W 

SE 2 E 

SW 2 W 

4t 

53 

26 

15 

NE f E 

NW f W 

SE f E 

SW 4 w 

5 

56 

15 

0 

ne by e 

nw by w 

se by e 

sw by w 

51 

59 

3 

45 

ENE | N 

WNW f N 

ESE f S 

wsw f s 

51 

61 

52 

30 

ENE 2 N 

WNW 2 N 

ESE 2 S 

WSW 2 s 

51 

64 

41 

15 

ENE 4 N 

WNW 1 N 

ESE 1 S 

wsw 1 s 

6 

67 

30 

0 

ENE 

WNW 

ESE 

wsw 

61 

70 

18 

45 

ENE 4 E 

WNW 4 W 

ESE \ E 

WSW 4 w 

61 

73 

7 

30 

ENE 2 E 

WNW 2 W 

ESE 2 E 

WSW 2 w 

« 

75 

56 

15 

ENE 1 E 

WNW t W 

ESE | E 

wsw t w 

7 

78 

45 

0 

e by N 

w by n 

e by s 

w by s 

74 

81 

33 

45 

E | N 

W 4 N 

E t S 

w | s 

71 

84 

22 

30 

E 2 N 

W 2 N 

E 2 S 

W 2 S 

71 

87 

11 

15 

E 1 N 

W 4 N 

E \ 8 

w 1 s 

8 

90 

0 

0 

EAST. 

WEST. 

EAST. 

WEST. 




























375 


THE ENGINEER’S HANDY-BOOK. 


H 

H 

P) 

•< 

E-f 


• 

cc 

Eh 

W 

£ 

H 

P 

P 

K 

m 

HH 

Eh 

P 

O 

ce 

W 

t—i 

Eh 

i—' 

O 

C 

i-3 

W 


0 

to 

< 


p 

p 

H 


to 

© 


w 

hr 

HH 

Eh 

© 


O 

— 

c/j 



o 

O 

O 

o 


O 

O 

o 

O 

1 

. 

O © 

W 

o P 

o 

o 

O 

o 


o 

o 

o 

O 

• 3 

o 

*s 

O 

•N 

o 

r\ 

o 

e. 

CO 

o 

ex 

o 

•X 

o 

<3 

C3 

to 


Of 1 

r—1 

rH 

3 

<©1 

t- 

Ob 

GO 


,« 05 

CO 

CM 

1—1 

O 

05 

CO 

CO 

05 

33 a 

F O 

Eh ^ 

•- CO 

r-H 

CO 

CO 

• P-H 

CO 

rH 

GO 

05 

2S o 

^ >o 

CO 

•s 

CO 

rs 

05 

c3 

ex 

LO 

•s 

CO 

LO 

43 © 

O Ch 
f-l 

CO 

CO 

05 

CO 

rH 

i> 

t— 

1- 

GO 

IQ 

l>- 

ex 

H 

L— 

G OQ 

0) H 

Q « 









rH 

CN 

•— 

3 






















Ph 











© i 

p £ 

cS 

o> 









rH 

Eh 











r 

H o 

u 










s © 

cL Ob 

(M 

05 

CO 

©1 

GO 

IQ 


CM 

Hf 3 

h i 

« w 

G - 

n CM 

OJ 

OJ 

rH 

rH 

rH 





3 

rz3 









3 


PH 

Ci 









r 











■4H 











i-t 











<u 

P 










H 

w 

« 






-i-P 

U 




3 

o> 

◄ 

p 

• 





3 

<V 

V* 


V* 


PH 

h{ 





a> 




■73 

O 

H-— 1 





rC 




r h 

°a 

!—i 

3 

a> 

v« 

>• 



■X* 

-4H 

rn 

^H 

3 




i 

33 

^ 3 

CO H 

w 

CD 

+■> 

>• 

v-> 


>• 

N# 

Ob 

hh> 

p 

a» 

>• 

>• 

X* 

x» 

X* 

a> 

S *70 

rn 

ft 

p-. 





H-P 




rH 

p « 

o 





3 





£ a 

© 





a> 

p 




e—« 

£ H 

03 





bO 




rr 

2 a 

H-P 

• «-H 





o 


xe 

xe 

V* 

x« 

V. o> 

- > 

CD 

S a 

a 

Ne 


X* 


«s 




03 

p 

w 

t> 

bC 

3 

s 




t® 

1 

o 

o 

CO 

LO 

o a 




Ei 

o 

o 

00 

o 

o 3 

hH 





^T 1 

o 


rH 

O PP 

Eh 

< 

P 

w 

PH 

O 

It- 

^3 

3 

c 


of 

c 

-4-P 

ICO 
r ICO 

rH 

r-i 



o* w 

O 2 1 

TO O 

P3 

’""H 

W 


-ft- 

P* 
















50 

(K 





o 





• f—>* 

G 

Ob 

o 

o 

1-0 

o 

o 

o 

o 

o 

o 3 

w 

* CO 

o 

o 

'rH 

i© 

o 

o 

o 

o 

O 3 ■ 

rH 

w 

a, ^ 

T — 1 

<3 

rH 

o 


o 

♦N 

C 3 

o 

•N 


s 

— CO 

1 - 

GO 

-t 

HH 

05 

o 

'H' 

t— 

£ $ 

00 H 

PH 

Q 





o 

CO 

ao 

t- 

CO 

CO 










• 

—v— 

CO 

s 









• 

Eh 





m 




<v 


W 

Px 




03 



CO 

e-i 

to 



• 

• 


Sh 


jm 

3 

< 

P 

PP 

3 

o 

?H 

a> 

CO 

3 

3 

© 

rH 

- 4 -P> 

*H 

C 3 

ro 

P 

3 

O 

Sh 

a> 

-u 

CO 

a 

H-J 

rH 

Saturn 

3 

3 

3 

3 

-u 

CP 

<D 

m 

o> 

r^ 


PH 

fp 

> 

w 

£ 

c 


P 


H 
























376 


THE ENGINEER’S HANDY- BOOK. 


Technical Terms and Definitions Used in Navigation. 

Apparent altitude. —The apparent altitude is the observed 
altitude, corrected for the indicated error of the instrument, and 
dip of the horizon. 

Meridian altitude. —The meridian altitude is the highest alti¬ 
tude a celestial object attains on the meridian of the observer. 

Observed altitude. — The observed altitude is the altitude of 
a celestial object above the horizon measured by a sextant or 
quadrant. 

True altitude. — The true altitude is the apparent altitude cor¬ 
rected for refraction and parallax. 

Amplitude. —The amplitude is the arch of the horizon con¬ 
tained between the centre of the celestial object, when risiug or 
setting, and the east or west points of the horizon, measured from 
the east when rising, and from the west when setting. 

Azimuth. — An azimuth is the angle at the zenith contained 
between the vertical circle passing through the centre of the ce¬ 
lestial object, and of the meridian of the place. 

Course. —The course is the direction steered by compass. 

Magnetic course. —The magnetic course is the compass course 
corrected for deviation of the compass. 

True course. —The true course is the compass course cor¬ 
rected for variation and deviation of the compass. 

Course made good. — The course made good is the compass 
course corrected for deviation, variation, leeway, and set of the 
current, and is the ship’s real track on the ocean. 


THE ENGINEER’S HANDY-BOOK. 


377 


Variation of the compass. — The variation of the compass is 
the angle between the true north and the magnetic north. There 
are only few places where the needle points exactly to the true 
north. When it points to the eastward of the true north, it is 
easterly variation ; but when the north point of the needle is at¬ 
tracted to the westward of north, it is called westerly variation. 

Deviation of the compass. —The deviation of the compass is 
the angle between the compass north and the magnetic north, and 
is produced by the local attraction of the ship’s iron on her com¬ 
passes. 

Declination. — The declination is the distance a celestial object 
is north or south of the equinoctial, measured on a meridian. 

Error of the compass. — The error of the compass is the va¬ 
riation and deviation combined. 

Dead reckoning. — The dead reckoning is the method of as¬ 
certaining the ship’s position by the courses steered and distance 
sailed, as shown in the following pages under the head of the 
Day’s Work. This is liable to many errors, such as bad steering, 
unknown currents, improper allowances made for distance run, 
and often fails to give the ship’s true position. 

Departure. —The departure is the distance in miles made good 
by a ship, east or west; when a ship sails due north or south, she 
makes no departure. 

Taking a departure. —When bearings are taken of some head¬ 
land or other known object, before a ship leaves the land, it is 
called taking a Departure. 

Distance. —Distance is the distance between two places or po¬ 
sitions, or the distance sailed by a ship on a certain course, meas¬ 
ured in nautical miles. 

Polar distance. —The polar distance is the distance of a ce- 
32* 


378 


THE ENGINEER’S HANDY- BOOK. 

lestial object from the elevated pole, and is found by subtracting 
the "declination of the object from 90°, when the latitude and the- 
declination are of the same name, but by adding the declination to 
90°, when they are of contrary names. 

Ecliptic. — The ecliptic is the apparent annual path of the sun 
in the heavens. 

Equator. —The equator is a great circle passing round the 
earth, 90 degrees from the poles, and dividing it into two equal 
parts or hemispheres, called the Northern and Southern Hemi¬ 
spheres. At all places on the Equator, the sun rises and sets at 
six o’clock all the year round. 

Visible horizon. —The visible horizon is the circle that bounds 
the observer’s view at sea, where sky and water appear to meet. 

Dip of the horizon. — The dip of the horizon is the angle be¬ 
tween the true and visible horizon, and is a correction which must 
be subtracted from all altitudes. 

Hour angle of a celestial object. — The hour angle of a ce¬ 
lestial object is the angle at the pole between the meridian of the 
observer and that of the celestial object. 

Latitude. —Latitude is distance north or south from the Equator, 
measured in degrees, minutes, and seconds on a meridian ; a place 
or position is in north or south latitude, according as it is north or 
south of the Equator; a degree of latitude is 60 nautical miles 
of 6082 feet. 

Parallels. —Parallels of Latitude are small circles parallel to 
the Equator, running round the earth east and west. Two places 
situated on one of these circles are said to be in the same parallel 
of latitude. 

Difference. —Difference of Latitude is the distance a ship 


THE ENGINEER’S HANDY-BOOK. 379 

makes good in a north or south direction. When two places or 
positions are on the same side of the Equator, that is, in north or 
south latitude, their difference of latitude is found by subtracting 
the lesser latitude from the greater; when two places or positions 
are on the opposite sides of the Equator, that is, when one is in 
north latitude, and the other in south latitude, their difference of 
latitude is found by adding the latitudes together. 

Leeway. — The leeway is the angle between the ship’s true 
course and her path through the water; starboard tack allows lee¬ 
way to the left hand; port tack allows it to the right hand. 

Longitude. — Longitude is the degrees, minutes, and seconds a 
place or position is east or west of the first meridian, measured on 
the Equator. Most nations adopt the Meridian of Greenwich ob¬ 
servatory in England as the first meridian. Thus the longitude 
of a place or position is called east or west of the Meridian of 
Greenwich, reckoned up to 180 degrees, which is the opposite me¬ 
ridian to Greenwich, or one-half of the circumference of the 
earth. Longitude is also reckoned by time,— hours, minutes, and 
seconds,— each hour being equal to 15 degrees of longitude, as the 
sun, which regulates the time, returns to the same meridian once 
in every 24 hours. Thus 15 degrees multiplied by 24 hours 
makes 360 degrees, the entire circumference of the earth. 

To reduce longitude into time. — Divide the number of de¬ 
grees, seconds, and minutes by 15, and the quotient will be the 
time. 

Degrees of Longitude. —The degrees of longitude are of the 
same length at the Equator as a degree of latitude, viz., 60 nau¬ 
tical miles; but as the meridians contract, and the distance be¬ 
tween them decreases gradually the farther you go north or south, 
until they meet at the poles, it is evident that the space contained 
in a degree of longitude becomes less the farther north or south 
the distance travelled. Thus in latitude 60° north or south, 30 
miles of departure is equal to a degree of longitude. It will be 


380 the engineer’s handy-book. 

seen that if a vessel sails 60 miles east or west in the parallel of 
60° north or south, she will make two degrees of longitude; in 
latitude of 70° north or south, 60 miles is equal to nearly three 
degrees of longitude. 

Difference of longitude. — The difference of longitude is the dif¬ 
ference in degrees, minutes, and seconds which one place or position 
is east or west of another ; when two places or positions are on the 
same side of the Meridian of Greenwich east or west, their dif¬ 
ference of longitude is found by subtracting the less from the 
greater. When they are on opposite sides of the Meridian of 
Greenwich, that is, one in east longitude and one in west longi¬ 
tude, their difference of longitude is found by adding the two to¬ 
gether. When one longitude is east and the other west, and on 
being added together the sum exceeds 180 degrees, it must be sub¬ 
tracted from 360 degrees to get the difference of longitude. 

Meridian. —A meridian is a circle passing through both poles, 
and crossing the Equator at right angles All places situated on 
this circle are on the same meridian, or in the same longitude 
north or south of each other. 

Parallax. —The parallax is the difference between the altitude 
of a heavenly body observed on the surface and what it would be 
if taken at the centre of the earth. 

Poles. —The poles are the extremities of the earth’s axis; 
these are 90 degrees north and south of the Equator, and are 
called the North and South Poles. 

Port side. — The term port side is used to designate the left 
hand side of the ship looking towards the bow. 

Refraction. — The refraction is the difference between the real 
and apparent places of heavenly bodies, as affected by the atmos¬ 
phere. 


881 


THE ENGINEER’S HANDY-BOOK. 

Right ascension. — The right ascension is the distance a ce¬ 
lestial object is east of the first point of Aries, measured on the 
equinoctial. 

Semi-diameter. — The semi-diameter is half the diameter of 
the sun or moon. It is given for each day in the Nautical Al¬ 
manac, and must be applied to all altitudes of the sun or moon to 
get the true central altitude. If the lower limb is observed, it 
must be added; if the upper limb, subtracted , and vice versa. 

Starboard side. — The term starboard side is employed to des¬ 
ignate the right hand side of a ship looking towards the bow. 

Augmentation. — The augmentation of the Moon’s semi-diam¬ 
eter is a correction to be added to the semi-diameter, as taken 
from the Nautical Almanac, on account of the moon being nearer 
to the observer when above the horizon than when in the horizon. 

Tropics. —The Tropics are that portion of the earth situated 
between 231° north and 231° south latitudes. 

Civil time. —Civil time is reckoned from midnight to noon, then 
called A. M. ; and from noon to midnight, then called P. M. The 
civil day commences at midnight; the nautical or sea day com¬ 
mences at noon, twelve hours before the civil day. 

Astronomical time. —Astronomical time is reckoned from noon 
to noon continuously, from 0 hour to 24 hours. 

Sidereal time. —Sidereal time is the hour-angle of the first 
point of Aries, west of the meridian. 

Apparent time. —Apparent time is time reckoned by the sun, 
which is subject to continual variations, and requires correction 
for astronomical purposes. 

Mean time. —Mean time is time regulated by the average or 
mean, instead of the unequal or apparent, motion of the sun, 


382 


THE ENGINEER’S HANDY-BOOK. 


and is such as would be shown by the sun if it moved uniformly 
in the equinoctial. 

Equation of time. — The equation of time is the difference be¬ 
tween apparent and mean time, is found in the Nautical Almanac 
for each day, and is used for reducing apparent time to mean 
time. 

Zenith distance. —The zenith distance is the distance a celes¬ 
tial object is from the zenith, or the point overhead. 


TABLE 


OF THE MILE AS MEASURED BY VARIOUS NATIONS. 


The English mile is 1760 yds. 

The Scotch “ 1984 “ 

The Irish “ 2240 “ 

The German “ 8106 “ 

The Dutch and Prus¬ 
sian mile is . . . 6480 “ 

The Italian mile is . 1766 “ 

The Vienna post mile 

is ..... . 8296 “ 
The Swiss mile is . 9153 “ 


The Swedish and 

Danish mile is . 7341*5 yds. 
The Arabian “ . 2143 “ 

The Roman mile is 

1628 or 2025 “ 
The Werst mile is 

1167 orl337 “ 
The Tuscan mile is 1808 “ 

The Turkish “ 1826 “ 

The Flemish “ 6869 “ 


The British league, or three times our geographical mile of 60 
to a degree, or 2025 yards, is 6075 yards. The Brabant league is 
6096 yards. The Danish and Hamburg league is 8244 yards; 
the German league is 8101 yards; the long German league is 
10126 yards; the short German league is 6859 yards; the Portu¬ 
guese league is 6760 yards; the Spanish league is 7416 yards; 
the Swedish league is 11700 yards. All of them are parts of a 
degree, but made before the length of a degree was accurately 
determined. 


Length of Days in Different Countries. 


At London, England, and Bremen, Prussia, the longest day has 
161 hours. At Stockholm, in Sweden, the longest day has 181 





THE ENGINEER’S HANDY-BOOK. 


383 


hours. At Hamburg in Germany, and Dantzic in Russia, the 
longest day is 18 hours, and the shortest is 7. At St. Petersburg 
in Russia, and Tobolsk in Siberia, the longest day has 19 hours, 
and the shortest, 51. At Tornea, in Finland, the longest day 
has 24 hours, and the shortest is a half-hour. At Wardbuys in 
Norway, the longest day lasts from the 1st of May to the 22d of 
July without interruption ; and at Spitzbergen the longest day 
is three months and a half. At New York the longest day has 
15 hours and 56 minutes; and at Montreal 151 hours. 


TABLE 


OF SAILING DISTANCES FROM NEW YORK TO DIFFERENT PARTS OF THE 

WORLD, IN GEOGRAPHICAL MILES. 


To Sandy Hook 

18 miles 

“ Nantucket Light 

. 211 

a 

“ Boston . . . 

302 

a 

“ Halifax . . . 

666 

a 

“ CapeHenlopen. 

149 

ii 

“ Philadelphia 

252 

ii 

“ Cape Henry 

276 

a 

“ Baltimore 

428 

ii 

“ Washington 

434 

ii 

“ Norfolk . . . 

306 

ii 

“ Richmond . . 

375 

ii 

“ Cape Hatteras . 

340 

ii 

“ Charleston . . 

621 

ii 

“ Savannah . . 

716 

ii 

“ Key West . . 

1,484 

ii 

“ Havana . . 

1,454 

ii 

“ New Orleans . 

2,129 

a 

“ Vera Cruz . . 

2,354 

a 

“ Liverpool 

3,084 

a 

“ London . . 

3,225 

a 


There are 5280 fe< 


To St. Petersburg, 4,420 miles. 
“ Havre . . . 3,148 “ 

“ San Francisco, 

via Panama, 5,249 
“ San Francisco, 
via Cape 
Horn. . . 18,850 “ 

“ Melbourne, via 
Cape of Good 
Hope . . 12,895 “ 

“ Nangasaki, Ja- 

pan . . . 9,800 “ 

“ Sandwich Isl¬ 
ands, via 
Panama. . 7,157 “ 

“ Canton, via 

Panama . 10,000 

“ Canton, via 

Good Hope, 19,500 “ 

in a statute mile. 







384 


THE ENGINEER’S HANDY-BOOK 


TABLE 

OF LATITUDE AND LONGITUDE OF PLACES. 


Places. 

Latitude. 

Longitude. 


I). M. 

n. m. 

Quebec. 

46 49 N. 

71 16 W. 

Halifax ..... 

44 38 “ 

63 65 “ 

Portland light .... 

43 36 “ 

70 12 “ 

Buffalo ..... 

42 53 “ 

78 55 “ 

Chicago. 

42 0 “ 

87 35 “ 

Newburyport light 

42 48 “ 

70 49 “ 

Boston State-House 

42 21 “ 

71 4 “ 

Nantucket light .... 

41 23 “ 

70 3 “ 

Newport ..... 

41 29 “ 

71 19 “ 

New York ..... 

40 42 “ 

74 0 “ 

Philadelphia .... 

39 57 “ 

75 10 “ 

Cape Henlopen .... 

38 46 “ 

75 4 “ 

Cincinnati ..... 

39 6 “ 

84 27 “ 

St. Louis ..... 

38 36 “ 

89 36 “ 

Richmond ..... 

37 32 “ 

77 27 “ M 

Washington City .... 

38 53 “ 

77 3 “ 3 

Baltimore ..... 

39 18 “ 

76 37 “ B 

Cape Hatteras .... 

35 14 “ 

75 30 “ ® 

Charleston light .... 

32 42 “ 

79 54 “ | 

Savannah ..... 

32 5 “ 

81 8 “ 3 

Cape Florida .... 

25 41 “ 

80 5 “!■ 

Pensacola ..... 

30 24 “ 

87 10 “ 

Mobile ...... 

30 42 “ 

87 59 “ 

New Orleans .... 

29 57 “ 

90 0 “ 

San Francisco .... 

37 47 “ 

122 21 “ 

Cape Horn ..... 

55 59 “ 

67 16 “ 

Porto Rico ..... 

18 29 “ 

66 7 “ 

Cape Hayti ..... 

19 46 “ 

72 11 “ 

Havana ..... 

23 9 “ 

82 22 “ 

Vera Cruz. 

19 12 “ 

96 9 “ 

Mexico ..... 

19 26 “ 

99 5 “ 

Porto Bello . 

9 34 “ 

79 40 “ 

Cape St. Augustine 

8 21 S. 

34 57 M 

Rio Janeiro ..... 

22 56 “ 

43 9 “ 

Buenos Ayres .... 

34 36 “ 

58 22 “ 


From Greenwich 















THE ENGINEER^ HANDY-BOOK. 


385 


TABLE — ( Continued .) 


OP LATITUDE AND LONGITUDE OF PLACES. 


Places. 

Latitude. 

Longitude. 

Cape Horn ..... 

D. M. 

55 59 S. 

D. M. 

67 16 W. 

Valparaiso .... 

33 2 N. 

71 41 “ 

London 

51 31 “ 

0 6“ 

Liverpool . 

53 22 “ 

2 52 “ 

Greenwich .... 

51 29 “ 


Dublin ...... 

53 23 “ 

6 20 W. 

Paris ...... 

48 50 “ 

2 20 E. 

Marseilles ..... 

43 18 “ 

5 22 “ 

Florence ..... 

43 46 “ 

11 16 “ 

Rome ...... 

41 54 “ 

12 27 “ 

Naples ...... 

40 50 “ 

14 16 “ hrj 

Berlin ...... 

52 31 “ 

13 24 “ § 

Hamburg ..... 

53 33 “ 

9 56 “ ~ 
16 23 “ f 

Vienna ...... 

48 13 “ 

Constantinople .... 

41 1 “ 

28 59 “ S 

Stockholm ..... 

59 21 “ 

18 4 “ 1 

Copenhagen ..... 

55 41 “ 

12 34 “ r 

St. Petersburg .... 

59 56 “ 

30 19 “ 

Madrid ..... 

40 25 “ 

3 42 W. 

Gibraltar ..... 

36 6 “ 

5 20 “ 

Lisbon ...... 

38 42 “ 

9 9“ 

Palermo ..... 

38 12 “ 

15 35 “ 

Pekin ...... 

39 54 “ 

116 28 E. 

Canton ...... 

23 7 “ 

113 14 “ 

Cape of Good Hope 

34 22 S. 

18 30 “ 

Sidney, Australia .... 

34 0 “ 

151 23 “ 

Jerusalem ..... 

31 48 N. 

37 20 “ 


TABLE 

SHOWING THE TIME AT DIFFERENT PLACES WHEN IT IS 12 O’CLOCK NOON AT NEW YORK. 


i 

Washington, D. C. 

Hours. 

11 

Min. 

47 

JSec. 

48 

A.M. 

San Francisco, Cal. 

8 

46 

13 

U 

Salt Lake Citv, Utah. 

9 

27 

36 

u 

Greenwich, Eng. 

4 

56 

0 

P.M. 

Liverpool, “. 

4 

43 

59 

U 

Paris, France. 

5 

5 

21 

u 


33 



























386 


THE ENGINEER’S HANDY -BOOK. 


TABLE 

OF MILES AND KNOTS, KNOTS AND MILES. 

The decimals of miles in this table are repeaters, and when four is used , the last 

figure should be increased by one. 


Knots. 

Miles. 

Miles. 

Knots. 

1 

1-1515 

1 

0-868421 

2 

2-3030 

2 

1*736842 

3 

3-4545 

3 

2-605263 

4 

4-6060* 

4 

3-473684 

,5 

5-7575 

5 

4-342105 

6 

6-9090 

6 

5-210526 

7 

8-0606 

7 

6-078947 

8 

9-2121 

8 

6-947368 

9 

10-3636 

9 

7*815790 

10 

11*5151 

10 

8-684211 

11 

12-6666 

11 

9*552632 

12 

13-8181 

12 

10-421053 

13 

14-9696 

13 

11*289474 

14 

16-1212 

14 

12 157895 

15 

17*2727 

15 

13-026316 

16 

18-4242 

16 

13-894737 

17 

19-5757 

17 

14-763158 

18 

20*7272 

18 

15-631579 

19 

21-8787 

19 

16-500000 

20 

23-0303 

20 

17-368420 

21 

24-1818 

21 

18-236841 

22 

25*3333 

22 

19-105262 

23 

26-4848 

23 

19-973683 

24 

27*6363 

24 

20-842104 

33 

38-0000 

38 

33-000000 


* There are 6080 feet in a knot. 


Marine Signals. 

While it must be admitted that we have made great improve¬ 
ment in the design and construction not only of* the hulls of steam¬ 
ships, but also of the machinery and all other appliances con- 

















THE ENGINEER’S HANDY-BOOK. 


387 


nected with their use, as a means of river, lake, and ocean naviga¬ 
tion, it is also an authenticated fact, that the number of marine 
disasters increases, especially as regards steamships, and that each 
succeeding year shows an increase in the loss of steamships as well 
as of human life and suffering. While light-houses illuminate 
almost every coast, yet signals of distress become more numer¬ 
ous and more dark, until the surf, as it were, is hoarse with the 
cries of drowning men. The questions may naturally be asked, 
in view of the foregoing facts, Have our ship-builders become 
more unscrupulous? the weather more changeable? or the sea 
more dangerous? Within the last thirty-seven years,fifty-six large 
ocean steamers have been wrecked, involving a loss of 4780 lives and 
over forty millions of dollars ’ worth of property , and oid of the whole 
number only two were lost from accidents to machinery. 

There are three classes of marine signals in use as a means of 
warning the mariner of his proximity to danger, viz., day signals, 
night signals, and fog signals. They address themselves to the 
eye and to the ear. Day signals, as a rule, are made with flags, 
as these furnish the simplest and probably the best medium of 
communication, whenever objects can be made out, and vessels 
are beyond hailing distance. Besides the light-house, there are 
three kinds of night signals used which produce sound, viz., the 
syren, the whistle, and the bell. The light-house, like the flag, 
is undoubtedly the most reliable and precise when the air is 
clear; but it frequently unfortunately happens that the strongest 
lights, even the most powerful electric lights, are often obscured 
and rendered invisible by fog. As a result, during heavy fogs by 
day or night, recourse must be had to instruments which produce 
sound, such as the syren, the whistle, and the bell. 

The theory with regard to their use is, that they are capable of 
emitting sounds of such intensity as to be heard at a distance suf¬ 
ficient to avert impending danger, providing that the officer of the 
watch is sufficiently wide awake to hear them. It frequently happens 
that the first indication that the mariner has of his approach to 
danger is a dull, muffled sound rising slightly above the roar of 


388 


THE ENGINEER’S HANDY-BOOK. 


the surf, the noise on board, or the wash of the water. He may 
be undecided as to the character of the sound, or from whence it 
arose, and, before giving orders, listens for its repetition, but dur¬ 
ing all this time the ship is rushing on to danger, or perhaps to 
destruction. Even if he should fully comprehend the nature of 
the sound and give orders, they may not be fully and quickly 
comprehended; the steamer may be sluggish in her movements, 
the engineer may not be at his post or close to the gear, or he may 
be drowsy and not fully understand the bells. Any of the fore¬ 
going circumstances may arise, and, though trivial in themselves 
under ordinary conditions, are of vital importance when a steam¬ 
ship, freighted with numerous lives and a valuable cargo, is rush¬ 
ing on to danger. Under such circumstances, courage, self-posses¬ 
sion, and that spontaneous knowledge of what to do in moments of 
extreme peril, are invaluable qualifications in the officer in charge. 

A steamship from three to four hundred feet in length, that 
steers well under full steam or sail, must receive a warning signal 
at least two miles from it in distance, as it will require a circle 
of at least 5000 feet, or T 9 0 of a mile, in which to turn such a 
vessel in smooth water; and it will take from ten to fifteen minutes 
to head her course directly opposite to the one in which she was 
steering when the signal was given, when she will be found to be 
nearly, if not quite, a mile from the line in which she was sailing 
when the helm was put hard over. It will take from seven to ten 
minutes to head her course in a direction at right angles to the 
one in which she was steering. In so doing she will describe a 
semicircle of at least half a mile, and, under the most favorable 
circumstances of wind and sea, it will take from five to ten minutes 
to head her square from danger. If all the surroundings were 
known, the same vessel might be stopped, backed, and be capable 
of reversing her motion in a period of five minutes. But it must 
be understood that the foregoing evolutions must be performed 
under the most favorable circumstances of sea, wind, weather, and 
sound, which goes to show that a signal to be efficient must be 
adapted to each and every one of the foregoing cases. 


THE ENGINEER’S HANDY-BOOK. 


389 


A proper system of lights and signals is of great importance, as 
they enable the mariner to shorten his voyage, and thus to facili¬ 
tate travel and cheapen freights. But what is needed is a system 
by which the signals might be placed by the side of the ordinary 
track of vessels, indicating to the mariner that he is right and in 
a position of safety. Vessels might approach such stations in 
safety, observe their number, and take a new departure from each, 
the result of which would be that the most dangerous highways 
of the sea, and the most intricate channels, might be navigated in 
the most foggy weather. 


Marine Whistle-Signals. 


When two steamships or boats are approaching each other 
from opposite directions, one puff of the whistle means keep to the 


right, thus , > which will bring the port, or red, light 

of each vessel in full view of the other. 

When two steamers are approaching each other from opposite di¬ 
rections, two puffs of the whistle mean go to the left, thus^ 



which will bring the green, or starboard, lights opposite each 
other. 

When two steamboats are moving in the same direction, one 
behind the other, and the hindermost one wishes to pass the steam¬ 
boat ahead, if one puff of the whistle is given, she passes ahead on the 

right side, thus __showing the red, or port, light of 

the passing boat and the green, or starboard, light of the boat 
being passed. Under the same circumstances, if two puffs of the 
whistle are given, it means that the hindermost boat is coming up 
on the left side, in which case the passing boat shows the star¬ 
board, or green, light, while the boat being passed shows the port, 
or red, light. 

Three puffs of the whistle is a salute, and four or more a call 

33 * 


390 


THE ENGINEER’S HANDY-BOOK. 

for an approaching steamer to slow down, stop, or come alongside, 
as the case may be. 

One long puff of the whistle is usually given when backing out 
of the dock, and one short puff is a call to the deck hand. 

Marine Bell-Signals. 

Steamboat bell-signals for engineers in the mercantile service 
are as follows: 

When the engine is at rest, on receiving one hell , the engineer 
starts ahead slowly, and continues until he receives a jingle-hell , 
which is a signal to steam at full speed. 

When running at full speed, one hell means to slow down, after 
which one hell signifies to stop. Under the same circumstances, 
two bells in succession signify stop , four hells in succession signify 
reverse and move backward at full speed. 

When the engine is at rest, two hells signify to go backward at 
full speed. If it is desired to go slowly backward, the orders are 
generally sent down through the speaking-tube, or communicated 
to the engineer by light or heavy taps on the gong. 

Light Signals for Ocean Steamships. 

When under way, a bright white light is fixed on the foremast, 

so as to show the light ten points on each side of the ship, a 
green light on the starboard side, and a red light on the port side, 
so constructed as to show the same number of points. 

Coasting steamers navigating the bays, lakes, rivers, or inland 
waters of the United States shall carry a bright light at the gaff- 
end or flag-staff, in addition to the side-lights. 

Steam-tugs, when towing, must carry two bright mast-head 
lights vertically (one above the other), in addition to their side¬ 
lights, so as to distinguish them from other steamships. 

Fog -signals. — Steamships, when under way, must use a steam- 
whistle at intervals of not more than one minute. Sailing-ships, 
when under way, must use a fog-horn every five minutes. 


THE ENGINEER’S HANDY- BOOK. 


395 


pitch of a screw, or the circumference of a paddle-wheel, multi¬ 
plied by the revolutions, and two figures cut off for decimals, gives 
the speed in knots per hour. 

The term left-handed propeller means a screw with a left-handed 
thread, and a right-handed one has a right-handed thread. A left- 
handed propeller, to move the ship ahead, goes from left to right, 
while a right-handed one turns from right to left, looking from 
the engine-room towards the stern of the boat. 

The force which drives a vessel forward when a screw-propeller 
is used, is the pressure exerted against the thrust-block. Steam 
being admitted to the cylinder, causes the piston to move, and 
the motion being transmitted through the connecting-rod to the 
crank-pin, crank, and propeller shafts, causes the latter to revolve, 
by which the pressure it exerts against the water is transmitted to 
the thrust-block, and the vessel forced forward. 

The term “ slip of the screw ” means the difference between 
the actual advance of the propeller through the water, and the 
advance which would be accomplished, if there was no recession 
of the water produced by the pressure of the propelling surface. 
A screw of 15 feet, if working in a stationary nut, would advance 
15 feet for every revolution ; but when it acts in the water, it may 
only advance 14 feet or less, the difference being caused by the 
water being pressed back, owing to its inertia being inadequate to 
resist the moving force. In such cases the slip is said to be 1 foot 
in 15, or nearly 7 per cent. loss. 

Measurement of the screw-propeller. — The surface of a screw- 
propeller is the same as would be generated by a line revolving 
around a cylinder, through the axis of which it passes, and at the 
same time advancing along the axis. To find the area of a pro¬ 
peller-shaft, square the diameter, and multiply by the decimal, 
•7854. 

The Errickson and Delameter propellers are those most gen¬ 
erally used, although the Loper Screw, as it is termed, is frequently 
employed, but it has now nearly gone out of use. 

The thrust-block of a propeller is formed of a series of rings, 


396 the engineer’s handy-book. 

generally of brass, with spaces between them, into which an equal 
number of solid collars fit. The thrust is exerted against the fore 
and aft faces of these rings and collars. 

The stern-tube is a tunnel located in the dead wood of a ship, in 
which the propeller-shaft revolves. Its outer end is made water-tight 
by a stuffing-box containing a fibrous packing. Stern-tubes were for¬ 
merly made of wood, but they are now generally made of boiler-plate. 

The Paddle-Wheel. 

The advantages of the paddle-wheel as a motive-power de¬ 
pend on the amount of the immersion. When the water ap¬ 
proaches the centre or reaches above it, it is obvious that great 
waste of power will ensue. It is quite as obvious that the 
greater the diameter of the wheel the greater the leverage, and 
the greater is the effect obtained. 

The slip of the paddle is caused by the recession of the water 
from the buckets, or it is a retrograde motion given to the water 
in a line parallel to the direction in which the ship is moving. 
The slip of the wheel is the difference between the speed of the 
ship and that of the wheel. The amount of slip is determined 
by finding the speed of the ship in feet per hour and subtracting 
it from the speed of the wheel at the centre of pressure, or centre 
of action, in feet per hour. 

The centre of action is that point in a wheel in which the effect 
would not be altered if the whole action of the water were con¬ 
centrated. The centre of action may be thus determined: Lay 
down the wheel to a certain scale and line off the dip on it. 
Take of the breadth of the totally-immersed paddles and | of 
the depth of those partially immersed, and add them ; their sum 
divided by the number of paddles partially or totally in the 
water will give the distance of the centre of action from the edge 
of the floats. This distance subtracted from the radius of the 
wheel, and multiplied by 2, will give the diameter of the centre 
of action of the wheel. The dip of the wheel is 69 inches, and, 
at that dip, there are 7 full-immersed floats and one immersed 


THE ENGINEER^ HANDY-BOOK. 


397 


15 inches, making 8 floats; depth of bucket, 21 inches. Find the 
speed of the circumference at the centre of action in the paddles 
in feet per hour; diameter of wheel, 36 feet; revolutions, 15 per 
minute. First take centre of action at ^ the mean depth of the 
immersed paddles, then l of 21 = 7, which, multiplied by 7, = 
49 ; i of 15 — 5 ; 5 X 1=5; 49 -f 5 = 54, which divided by 8, 
the number of buckets, = 6*75, which is the distance of the centre 
of action from the outer edge of the floats. Then 6*75 x 2 = 
13*5 inches; 36 feet = 432 inches; and 432 —13'5 = 418*5 -s- 12 
= 34*883, which is the diameter of the centre of action of the 
paddles, and this X 3*1416 = 109*5884, which is the circumference 
of their centre of action. Then 109*5884 feet X 15 revolutions 
X 60 minutes in an hour = 98,629 ft., the speed of circumference 
at the centre of action of the paddles in feet-power as required. 

The speed of the ship being 121 miles per hour, the percentage 
of slip of the above wheel may be calculated thus: 6082*66 ft. is 
a nautical mile, which multiplied by 121 = 74,512*58 = speed of 
ship in feet per hour. Then the speed of the centre of circum¬ 
ference of action in feet per hour is 98,629 — 74,512*58 speed of 
ship = 24,116*42, slip of centre of action of paddles in feet per 
hour. The percentage of slip would then be 93,629 : 24,116*42 
:: 100 : 24*44, which is the percentage of slip. 

Loss from oblique action is the loss in the common radial wheel 
occasioned by the floats striking the water at an angle. Oblique 
action consists of a vertical depression and lifting of the water by 
the entering and emerging floats. This loss is calculated by the 
square of the sines of the angles at which the buckets strike or 
enter the water. This may be explained as follows: When a body 
strikes obliquely on a plane, the force of impact with any given 
velocity varies according to the sines of the angle of incidence, 
and therefore the force with which the particles of water strike 
against a board will vary according to the sines of the angles at 
which they strike. This force is gradually growing less as the 
board is turned on its edge. The number of particles striking 
the board also vary according to the sines of the angles of inci- 
34 


398 


THE ENGINEER’S HANDY-BOOK. 


dence, or, in other words, according to the perpendicular height 
of the inclined board; so that the resistance, as it varies both with 
the force with which the particles strike the board and the number 
of particles which strike it, must vary according to the squares 
of the sines of the angle of incidence. This loss from oblique 
action may be obviated by using the feathering wheel, in which 
each float is hung upon a centre, and so arranged, by a suitable 
mechanism, as to be always in a vertical position. 

The rolling-circle of a wheel is a circle whose circumference 
multiplied by the number of revolutions of the wheel in a given 
time equals the speed of the vessel in the same time; or it is a circle 
at any point in the circumference, which moves with the same ve¬ 
locity as the speed of the ship. The diameter of the rolling-circle 
of a wheel is found as follows: Divide the speed of the ship in 
feet per hour by the number of revolutions per hour; the quotient 
will be the circumference of the rolling-circle; 10 X 5'280 = 
52*800-^600 (number of revolutions per hour) — *88, the circum¬ 
ference of the rolling-circle; and *88 -=-3*1416 = 28*01,the diameter 
of a rolling-circle. A disconnecting-paddle engine is one in which 
the paddle-wheel can be thrown out of gear by sliding back a clutch 
on the main-shaft. The crank-pin is made fast in the outer shaft, 
and, if desired to stop one engine, the throttle is shut, and the 
clutch on the shaft slipped back, which enables either engine to 
be reversed or stopped independently of the other. 

The names of the different paddle-wheels are the cycloidal, the 
manly, the radial, and the feathering. The two former, though pos¬ 
sessing some good features, for certain reasons have never come into 
very general use, while the latter are almost universally adopted. The 
feathering wheel is capable of producing more useful effect with less 
power than the radial wheel, but it has the disadvantages of great 
weight, extra first cost, as well as great expense of maintenance. 

The usual rule for calculating the horse-power of an engine 
cannot be applied to calculate the actual horse-power available 
for propelling a vessel, as much of this power is lost by the slip 
of the wheel and the oblique action of the buckets. 


THE ENGINEER’S HANDY-BOOK. 


399 


Comparative efficiency of the screw-propeller and paddle-wheel .— 
When a vessel is propelled through the water, she necessarily puts 
a column of water into motion in the direction of her advance. 
In the case of paddle-wheels, none of the power expended in pro¬ 
ducing the current is recovered; but with the screw the case is 
different, as the effect of the current reduces the number of rota¬ 
tions requisite for the production of any prescribed speed. In 
short vessels, in consequence of the rubbing surface of the bottom 
not being sufficient to generate a current, there is little difference 
between the performances of the paddle and screw; but in long 
vessels, where the water is more effectually rubbed into motion, 
the superior efficiency of the screw over any species of side pro¬ 
peller becomes very conspicuous. 

In the early trials between paddle- and screw-vessels, the two 
instruments appeared to be of about equal efficiency. This com¬ 
parison was made between the screw and radial paddle. But with 
the feathering paddle the efficiency is found to be greater in con¬ 
sequence of the floats entering and leaving the water edgewise. 
Feathering wheels have the further advantage for river navigation, 
that, as the diameter of the wheel may be reduced without giving 
rise to other difficulties, the speed of the engine may be increased. 

In vessels of moderate dimensions, the screw is found to be of 
about equal efficiency to the radial paddle, and of somewhat infe¬ 
rior efficacy to the feathering paddle; but in vessels of large size, 
the screw is found to be of considerably greater efficacy than pad¬ 
dles of any kind. 

Relation between the power and speed of steam-vessels. — When 
the relation between the pitch of the screw and the speed of the 
vessel is considered, and also that the pitch must be determined 
and the screw made before the vessel is tried, it must be obvious 
how important it is that marine engineers should clearly under¬ 
stand the laws affecting the motion of solid bodies in fluids. A 
few words will not, therefore, be out of place on this important sub¬ 
ject. When a steamboat makes a voyage between port and port, 
she in effect excavates a canal between those ports, the transverse 


400 


THE ENGINEER’S HANDY-BOOK. 


section of which corresponds with the immersed midship section 
of the vessel. It is true this canal is immediately filled up again, 
but yet this canal is really cut, and the work of the engine is ex¬ 
pended in cutting it. After uniform motion has been attained by 
the vessel, the work of the engine is transferred to the water pushed 
out of the canal. Now, for similar speeds, the work per mile, or 
per hour, must be as the immersed midship section of the vessel. 

Effect of size on the speed of steam-vessels. —All experiments 
confirm the theory, that to give one body twice the velocity of an¬ 
other, it will necessarily require the expenditure of four times the 
amount of energy. Assuming that fluid bodies follow, with re¬ 
spect to motion, the same laws as solids; if two vessels are making 
voyages, having the same immersed midship section, they will dis¬ 
place similar quantities of water from their course, regardless of 
speed. The water having motion given to it, the power ex¬ 
pended will be in proportion to the square of the velocity given 
to it. 

To find the mean speed of a steam-vessel. — The mean speed of a 
steam-vessel, from a number of runs over a measured knot where 
the tidal influence is always varying, may be ascertained as fol¬ 
lows : Add the different speeds for the trials, and divide by the 
number of trials. This will give the approximate mean speed. 

The great difficulty with paddle-wheels is to secure a proper 
immersion. As the ship proceeds on its voyage, and consumes 
its store of coal, the vessel becomes lighter, and consequently its 
draught of water decreases. Therefore, supposing a paddle is 
properly immersed at the commencement of a voyage, it will be 
partially out of the water at the end. At the commencement of 
a voyage, the paddle must be too deeply immersed, so that at the 
middle the proper immersion may be attained, while there will 
be too little towards the end of the voyage. The paddle-wheel 
is fast giving place to the screw-propeller, for the reason that it 
offers greater resistance to the wind in case of storm, thus inducing 
oscillation of the vessel, besides being more exposed to the shots 
of an enemy in time of war. 


THE ENGINEER’S HANDY-BOOK. 


401 


Pumps. 

Pumps, of whatever design or construction, or for whatever pur¬ 
pose employed, are simply hydraulic machines attached to one 
end of a tube, for the purpose of raising, 
forcing, or transferring water, or other 
liquids or fluids. The idea entertained 
by many that water is raised by suction 
is erroneous, as, properly speaking, there 
is no such principle as suction. Atmos¬ 
pheric “ lift ” or “ suction ” pumps cause 
the water to raise itself by having its 
surface relieved of the column of air 
resting upon it. If, therefore, one end of a pipe or tube be lowered 
into water, the other end be closed by means of a valve or other 
device, and the air contained in the pipe be drawn out, it is evi¬ 
dent that the surface of the water within the pipe will be relieved 
of the pressure of the atmosphere. There will then be no resist¬ 
ance offered to the water to prevent its rising in the tube. The 
water outside of the pipe, still having the pressure of the atmos¬ 
phere upon its surface, therefore forces water up into the pipe, sup¬ 
plying the place of the excluded air, while the water inside the 
pipe will rise above the level of that outside of it, proportionally 
to the extent to which it is relieved of the pressure of the air; so 
that, if the first stroke of a pump reduce the pressure of the air 
contained in the pipe from 15 pounds per square inch (which is its 
normal pressure) to 14 pounds, the water will be forced up the pipe 
to the distance of about 21 feet, since a column of water an inch 
square, and 21 feet high, is equal to about one pound in weight. 

It is evident that, upon the reduction of the pressure of the air 
contained in the pipe from 15 to 14 pounds per square inch, there 
will be (unless the water ascended the pipe) an unequal press¬ 
ure upon its surface inside as compared to that outside of the 
pipe; but, in consequence of the water rising 21 feet in the pipe, 
the pressure on the surface of the water, both inside and outside, 
34 * 2 A 











402 


THE ENGINEER’S HANDY-BOOK. 


is evenly balanced (taking the level of the outside water to be the 
natural level of the water inside), as the pressure upon the water 
exposed to the full atmosphere is 15 pounds upon each square 
inch of its surface, while that upon the same plane, but within 
the pipe, will sustain a column of water 21 feet high (weighing 
one pound) and 14 pounds pressure of air, making a total of 15 
pounds, which is, therefore, an equilibrium of pressure over the 
whole surface of the water at its natural level. 

If, in consequence of a second stroke of the pump, the air 
pressure in the pipe is reduced to 13 pounds per inch, the water 
will rise another 21 feet. This rule is uniform, and shows that 
the rise of a column of water within the pipe is equal in weight 
to the pressure of the air upon the surface of the water without; 
hence it is only necessary, to determine the height of a column of 
water that will weigh 15 pounds per square inch of area at the 
base, to ascertain how far a suction-pump will cause the water to 
rise. It must be understood, that the distance varies with the 
height above sea level, and also with the pressure of the atmos¬ 
phere. At our level of the sea, the column of water that the 
atmosphere will support is about 33 feet in height, and a pump 
will “ draw water ” (as it is called) this distance; but the force 
which sends the water into the pump at this height is so dimin¬ 
ished as to be almost balanced by its own weight; hence a lifting- 
pump will deliver water very slowly, drawing it this distance. 

To be reliable, the cylinder and piston should be in good order, 
all the joints perfectly air-tight, a check-valve be placed in the 
lower end of the suction-pipe; and even then the pumps should 
be run at a high speed. Pumps will give more satisfactory results 
when the lift is from 22 to 25 feet. There is hardly any limit to 
the distance a pump will draw water through a horizontal suction- 
pipe, provided the pipe is perfectly tight, and everything is so pro¬ 
portioned as not to cause undue friction. 

The capacity of any pump may be determined by multiplying 
the area of the piston in inches by its stroke in inches, giving the 
number of cubic inches per single stroke; this divided by 231 (the 


THE ENGINEER’S HANDY-BOOK. 


403 


number of cubic inches in a standard gallon) will give the number 
of gallons per single stroke; but it must be remembered that all 
pumps throw less water than their capacity, the deficiency rang¬ 
ing from 20 to 40 per cent., according to the quality of the pump. 
This loss arises from the lift and fall of the valves, from inaccuracy 
of fit or leakage, and in many cases from there being too much space 
between the valves and piston, or plunger. The higher the valves 
of any pump have to lift to give the necessary opening, the less 
efficient the pump will be. 

The power required to raise a given quantity of water a certain 
height may be computed by the following rule: Multiply the 
amount of water in gallons to be raised per minute by 8’35 lbs. 
(the weight of a gallon of water), and this product by the height, in 
feet, of the discharge from the point of suction; divide the result by 
33,000, which will give the theoretical horse-power required to raise 
the amount of water to a certain distance. See table on page 522. 

The quantity of water which any pump will lift, or discharge, 
may be estimated by multiplying the area of the piston by the 
speed; but this rule infers that the pump is fully supplied, and 
the w T ater thoroughly discharged at every stroke. 

Rule for finding the diameter of pump-plunger for any engine.— 
When the pump-stroke is ^ the stroke of the engine, the diameter 
of the steam-cylinder multiplied by 0*3 will give the proper di¬ 
ameter of’ pump-plunger. 

Another rule. — When the pump-stroke is \ of the stroke of the 
engine, the diameter of the cylinder multiplied by *42 will give 
the proper diameter of pump-plunger. 

Diameter of pump-plunger should be equal to | the diameter 
of the cylinder when the pump-stroke is b the engine-stroke. 

Diameter of pump-plunger should be equal to ^ of the diameter of 
the cylinder when the pump-stroke is ^ the engine-stroke. The ve¬ 
locity of water in pump-passages should not exceed 500 feet per min¬ 
ute. Pump-valves should have an area of | the area of the pump. 

Feed-pumps for condensing engines. —For condensing engines, 
the diameter of the pump-plunger should equal I'll the diameter 


404 


THE ENGINEER’S HANDY-BOOK. 


of the steam-cylinder when the pump-stroke is half the engine- 
stroke, and -J- the diameter of steam-cylinder when the pump-stroke 
is | the stroke of the engine. 

Rule to find the diameter of the feed-pump ram. — Multiply 

the square of the diameter of the cylinder in inches by '0083. 
The product is the diameter of the ram in inches. All boiler 
feed-pumps, when working at ordinary speed, should be capable 
of discharging one cubic foot of water per horse-power per hour. 

Rule for finding the necessary quantity of water per minute for 
any engine. — Multiply the cubic space in the cylinder in inches, 
to which steam is admitted before being cut off, by twice the num¬ 
ber of revolutions per minute, and divide the product by the com¬ 
parative volume of steam at the pressure used ; the quotient will be 
the cubic inches of water required per minute. 

A circulating-pump is used to lift water from the sea and force 
it through the condenser. Such pumps are not always worked by 
the main engines, but sometimes are independent or worked by an 
independent auxiliary engine. See cut on page 352. 

Although a pump will require to be in good condition to lift 
water 33 feet, it will with ease draw water on a level at 1000 feet 
(providing the pipes are all tight), and force it to any height that 
the machinery of the pump is capable of bearing. 

The reason why pumps do not work is, either that the water- 
supply is exhausted, the pipes or pistons leak, or the valves pre¬ 
vented from seating. If the valves and connections of a pump 
are tight and in good order, and it is not located too high above 
the supply, there is no reason why it should not work. 

Pumps become hot from two reasons,— either they are placed 
too near the boiler, or the pump and check-valves leak, and allow 
the hot water to escape back from the boiler into the barrel of the 
pump, which has the effect of expanding the valves and prevent¬ 
ing them from doing their work. 

A boiler feed-pump, or injector, for any engine should be capa¬ 
ble of supplying one cubic foot of water per horse-power per hour. 
Engines, in general, do not use that amount; in fact, the better 


THE ENGINEER’S HANDY-BOOK. 


405 


class of automatic cut-off engines will develop a horse-power with 
a water-consumption of from 25 to 30 lbs.; but it is always best 
to have the pump or injector sufficiently large, so that, in case the 
power should be increased, it may be equal to the demand. 

An air-chamber is placed on a pump to cushion the water-piston, 
and relieve the jar that would be induced by the pump-piston 
striking against a solid column of water; but, to produce the 
desired effect, it must be perfectly air-tight, otherwise the air 
will escape. Even when the air-chamber is perfectly air-tight, 
they require to be frequently refilled, as in fast-running pumps 
and fire-engines the air becomes condensed. This may be done 
by stopping the engine or pump, opening a cock or valve that 
connects with it, and allowing the air to rush in. There is a very 
general impression among engineers and those having charge of 
fire-engines, that there is a vacuum in the air-chamber, and the 
remark is often heard that the pump or engine has lost its vacuum. 
This is a mistake, as there is no such thing as a vacuum in the 
air-chamber of a steam-pump or fire-engine. The air-chamber 
has lost its supply of air either by leakage or condensation. The 
result is the pump commences to work and labor. 

A feed-pump pet-cock, or valve, is a small cock, generally 
placed on the barrel of the pump above the suction-valve, for the 
purpose of ascertaining whether the pump is working right or not. 

Mud-boxes, strainers, or arresters should be attached to the 
extreme end of all lift-, suction,- bilge-, or circulating-pumps, for 
the purpose of arresting any matter that would be liable to choke 
the pump or prevent the valve from seating. 

How to keep pipes and pumps from freezing.— The only certain 
preventive is the removal of the water from them; consequently, 
in all cases provision should be made for turning it off during 
very severe nights. It must be observed, however, that merely 
shutting off the water is not sufficient; it must all be let out of 
the pipes. For this purpose a small tap or pet-cock should be 
placed above the main stop-cock, or the latter should be made 
with a vent, to allow the water to flow out when it is turned off. 



406 


THE ENGINEER’S HANDY-BOOK. 


Injectors. 

The injector, though simple in design, modest in appearance, 
and diminutive in size, is, nevertheless, one of the most wonderful, 
important, and useful machines which the mechanical arts have 
ever presented to man. It consists of a slender tube, called the 
steam-tube, through which steam from the boiler passes to another 
or inner tube, called the receiving-tube. The latter tube conducts 
a current of water from the pipe into the body of the injector. 
Opposite the mouth of this second tube, and detached from it, is 
a third fixed tube, called the delivery-tube. This tube is open at 
the end facing the water-supply and leading from the injector to 
the boiler. 

Its action is identical to that of the steam-jet, or blower-pipe in 
the chimney of the locomotive. The principle is, that steam being 
admitted to the inner tube of the injector, enters the mouth of a 
combining-tube in the form of a jet, near the top of the inlet water- 
pipe. If the level of the water be below the injector, the escaping 
jet of steam, by its superficial action (or friction) upon the air 
around it, forms a partial vacuum in the combining-tube and inlet- 
pipe, and the water then rises by virtue of the external pressure of 
the atmosphere. Once risen to the jet, the water is acted upon by 
the steam in the same manner as the air has been seized and acted 
upon in first forming the partial vacuum into which the water rose. 

Giffard was the first to make a practical application of the prin¬ 
ciples embodied in the injector; in fact, when he invented his in¬ 
jector, he may be said to have invented them all. His discovery 
was, that the motion imparted by a jet of steam to a surrounding 
column of water was sufficient to force it into the boiler from 
which the steam was taken, and, indeed, into a boiler working at 
even a higher pressure. It is not at all extraordinary to see in¬ 
jectors, attached to boilers carrying a pressure of 70 or 80 lbs. per 
square inch, forcing water into other boilers under a pressure of 
250 lbs. per square inch. This extraordinary accumulation of 
power may be explained as follows: the velocity with which steam 


THE ENGINEER’S HANDY-BOOK. 


407 


say at 60 lbs. pressure to the square iuch — flows into the atmos¬ 
phere is about 1700 feet per second. Now suppose that steam is 
issuing, with the lull velocity due to the pressure in the boiler, 
through a pipe an inch in area, the steam is condensed into water, 
at the nozzle of the injector, without suffering any change in its 
velocity. From this cause its bulk will be reduced, say 1000, 
and therefore its area of cross-section — the velocity being constant 

will experience a similar reduction. It will then enter the boiler 
by an orifice jqVq part of that by which it escaped. Now it will 
be seen that the total force expended by the steam through the 
pipe on the area of an inch, in expelling the steam-jet, was con¬ 
centrated upon the area yoW °f an hich, and therefore was greatly 
superior to the opposing pressure exerted upon the diminished area. 

The invention of the Giffard Injector, like that of the Corliss 
engine, suggested a numerous progeny. This may be seen from the 
numerous cuts of that class of machines illustrating this work, but 
Sellers’ Injector is the only one that can be said to be an improve¬ 
ment on Giffard’s. All the others are simply modifications of the 
original Giffard instrument, some few bringing out features which 
had not been contemplated by Giffard, who considered Wm. Sell¬ 
ers’ improvements the only ones that had been made upon his in¬ 
strument. 

Injectors may be divided into three classes — “self-adjusting,” 
“adjustable,” and “fixed-nozzle.” The self-adjusting injector reg¬ 
ulates itself to meet all the conditions under which it is intended 
to work, and, once started, it will work under a variation of steam- 
pressure of from 10 to 150 lbs. This kind of injector furnishes 
the most reliable boiler-feeder. The adjustable injector is one in 
which the nozzle can be adjusted to meet the requirements of vary¬ 
ing steam-pressure and water-supply. Such injectors are capable 
of high duty when skilfully managed. The original Giffard rep¬ 
resents this type of injector. 

The injector possesses many advantages as a boiler-feeder for 
furnishing large quantities of water, supplying tanks, etc. Its first 
cost is moderate, it occupies but little space, and requires no oil. 



408 


THE ENGINEER’S HANDY-BOOK. 

packing, or repairs. It can be set up almost anywhere and placed 
either vertically or horizontally ; the latter position, however, is 
preferable. It will act longer, and perform more work even 
when abused and neglected, than any other device heretofore 
invented as a boiler-feeder. 


William Sellers & Co.’s Injector. 

The cut on page 409 represents Sellers’ celebrated lifting in¬ 
jector, so extensively used on locomotives, steamships, tugs, and 
ferries. It is a self-contained instrument, that is to say, it has 
both steam- and check-valves, so that it can be connected directly, 
without any other fittings; although, of course, it is desirable to 
place another stop-valve in the steam-pipe and a check-valve in 
the delivery-pipe, so that the injector can be taken to pieces, or 
disconnected at any time. Another important feature of this in¬ 
jector is, that it is operated by a single handle, and that the waste- 
valve is only open at the instant of starting. 

Its internal mechanism and mode of action may be easily un¬ 
derstood by referring to the sectional cut on page 410. A is the 
receiving-tube, which can be closed to the admission of steam by 
the valve X. A hollow spindle passing through the receiving- 
tube into the combining-tube, is secured to the rod B, and the 
valve X is fitted to this spindle in such a way that the latter can 
be moved a slight distance (until the stop shown in the figure 
engages with valve X) without raising the valve X from its seat. 
A second valve, W> secured to the rod B, has its seat in the upper 
side of the valve X, so that it can be opened (thus admitting steam 
to the centre of the spindle) without raising the valve X from its 
seat, if the rod B is not drawn out any farther after the stop on 
the hollow spindle comes in contact with the valve X. D is the 
delivery-tube, 0 an overflow opening into space C K , the check- 
valve in delivery-pipe, and P R the waste-valve. The upper end 
of the combining-tube has a piston, N N, attached to it, capable 
of moving freely in a cylindrical portion of the shell, M M, and 


William Sellers & Co.’s Lifting- Injector. 



409 


THE ENGINEER’S 


handy-book. 


35 
















































































410 


THE ENGINEER’S HANDY-BOOK 



/ 


Section of William Sellers & Co.’s Lifting Injector. 


































THE ENGINEER’S HANDY-BOOK. 


411 


the lower end of the combining-tube slides in a cylindrical guide 
formed in the upper end of the delivery-tube. 

The rod B is connected to a cross-head which is fitted over 
the guide-rod, J, and a lever, H, is secured to the cross-head. A 
rod, A, attached to a lever on the top end of the screw waste-valve 
passes through an eye that is secured to the lever H ; and stops, 
T ', Q, control the motion of this rod, so that the waste-valve is 
closed when the lever H has its extreme outward throw, and is 
opened when the lever is thrown in, so as to close the steam-valve, 
X, while the lever can be moved between the positions of the stops, 
P, Q , without affecting the waste-valve. A latch, V, is thrown 
into action with teeth cut in the upper side of the guide-rod, J, 
when the lever H is drawn out to its full extent, and then moved 
back; and this click is raised out of action as soon as it has been 
moved in far enough to pass the last tooth on the rod J. An air- 
vessel is arranged in the body of the instrument, as shown in the 
figure, for the purpose of securing a continuous jet when the in¬ 
jector and its connections are exposed to shocks, especially such 
as occur in the use of the instrument on locomotives. 

The manipulation required to start the injector is exceedingly 
■simple,— much more so in practice, indeed, than it can be rendered 
in description. Moving the lever H until contact takes place be¬ 
tween valve X, and stop on hollow spindle, which can be felt by 
the hand upon the lever, steam is admitted to the centre of the 
spindle, and, expanding as it passes into the delivery-tube D, and 
waste-orifice P, lifts the water through the supply-pipe into the 
combining-tube around the hollow spindle, acting after the manner 
of an ejector or steam-siphon. As soon as solid water issues through 
the waste-orifice P, the handle H may be drawn out to its full ex¬ 
tent, opening the steam-valve X and closing the waste-valve, when 
the action of the injector will be continuous as long as steam and 
water are supplied to it. 

To regulate the amount of water delivered, move in the lever 
U until the click engages any of the teeth on the rod J, thus 
diminishing the steam-supply, as the water-supply is self-regulat- 


412 


THE ENGINEER’S HANDY-BOOK. 


ing. If too much water is delivered, some of it will escape through 
0 into C, and, pressing on the piston N N, will move the com- 
bining-tube away from the delivery-tube, thus throttling the water- 
supply; and if sufficient water is not admitted, a partial vacuum 
will be formed in C, and the unbalanced pressure on the upper side 
of the piston, N N, will move the combining-tube towards the de¬ 
livery-tube, thus enlarging the orifice for the admission of water. 
The injector, once started, will continue to work without any further 
adjustment, delivering all its water to the boiler, the waste-valve 
being kept shut. By placing the hand on the starting-lever, it is 
easy to tell whether or not the injector is working; and if desired, 
the waste-valve can be opened momentarily by pushing the rod L , 
a knob on the end being provided for the purpose. 

TABLE 


SHOWING STEAM-PRESSURE REQUIRED TO LIFT AND DELIVER WATER WITH 
SELLERS’ FIXED-NOZZLE LIFTING INJECTOR. 


Height Wa¬ 
ter IS LIFTED. 

Steam-Press¬ 
ure required 

TO LIFT AND DE¬ 
LIVER Water. 

Height Wa¬ 
ter IS LIFTED. 

Steam-Press¬ 
ure REQUIRED 
TO LIFT AND DE¬ 
LIVER Water. 

Feet. 

Inches. 

Lbs. per Sq. In. 

Feet. 

Inches. 

Lbs. per Sq. In. 

3 

0 

25 

21 

3 

52 

5 

0 

30 


C 

60 

11 

6 

40 

22 

10 1 

70 

15 

0 

49 


l 

100 


Sellers’ Non-Adjusting Fixed-Nozzle Injector with Lifting 
Attachment, for Stationary Boilers. 

The cut on page 413 represents Sellers’ Non-Adjustable In¬ 
jector with fixed-nozzle and lifting attachment. As will be ob¬ 
served, a steam-ejector or siphon is attached to the side of this 
instrument, which draws the water, when lifted by the admission 
of the steam, through the combining-tube, and discharges it 
through the orifice of the lifting attachment, through which, also, 











THE ENGINEER’S HANDY-BOOK. 


413 



the waste water or overflow escapes. This injector has a check- 
valve connected to it, also a steam stop-valve, which can be opened 
wide by half a revolution of the lever on the stem. In connecting 
the injector, since it has fixed nozzles, a water-supply valve must 
be provided, and, as al¬ 
ready remarked, a sec¬ 
ond check-valve in the 
delivery - pipe and an¬ 
other steam-stop valve 
are desirable. 

In starting this injec¬ 
tor, steam is first admit¬ 
ted to the lifting-nozzle, 
the water-supply valve 
being adjusted so as to 
deliver about the max¬ 
imum amount of water 
corresponding to the 
steam-pressure; and as 
soon as solid water is¬ 
sues from the lifting- 
nozzle, the steam-valve 
is to be opened slightly 
until the jet is estab¬ 
lished, when the full 
steam-pressure is to be 
admitted, and the valve 
that admits steam to the 
lifting-nozzle is to be 
closed. 

Some little dexterity Section of Sellers’ Non-Adjustable Fixed- 
is required to start the Nozzle Lifting 1 Injector. 

injector for a maximum lift, but the manipulation is readily ac¬ 
quired, while for all ordinary lifts no special care is required. As 
the velocity of steam escaping from an orifice varies greatly with 


35 * 




















414 


THE ENGINEER’S HANDY-BOOK. 



the pressure, other things being equal, the lifting-nozzle must have 
proportions depending on the minimum steam-pressure to be em¬ 
ployed, since it can readily be adapted to higher pressures by par¬ 
tially closing the steam-admission valve. 

Directions for operating Sellers’ non-adjustable fixed-nozzle 

injector, with lifting at¬ 
tachment. — First , close 
the steam-spindle, A, 
by means of the handle, 
B. Second, open the lift¬ 
ing-jet by backing the 
wheel, C, one-quarter 
turn. Third, when the 
water escapes at the 
overflow, D , run out 
the spindle, A , by back¬ 
ing it quickly; then 
close the lifting-jet, C, 
as the injector will then 
be feeding the boiler, 
and the water-supply 
may be regulated by 
means of an ordinary 
globe-valve placed be¬ 
tween the injector and 
the water source. If 
this valve is set to ad¬ 
mit the required quan¬ 
tity of water, there will 
be no drip from the 
overflow. When re¬ 
quired, a special regu¬ 
lating valve, which re¬ 
quires but one turn, and which indicates the required opening, is 
attached to the injector, so that those having it in charge may de- 


Sellers’ Non-Adjustable Fixed-Nozzle 
Lifting 1 Injector. 








































































































THE ENGINEER’S HANDY-BOOK. 


415 


termine the actual amount of opening by a glance at the hand- 
wheel on the valve-spindle. 

Duty of Sellers’ injectors, or the foot-pounds of useful work 
performed by the consumption of 100 lbs. of coal in the boiler 
supplying steam to the injector, may be of interest. When the 
evaporation of the boiler is known, this duty can readily be com¬ 
puted from the data obtained in connection with the maximum 
delivery of the injector. This can be illustrated by an example. 
Assuming the boiler evaporation at 9 lbs. of steam per lb. of coal, 
a result which, though rather above the average, is occasionally 
exceeded in good practice. Using the data recorded in the table 
on page 416 for the maximum delivery at a steam-pressure of 130 
lbs. per square inch, it appears that 150 — 66 = 84 units of heat 
were imparted to each pound of water delivered by the injector, 
and, the weight of a cubic foot of water at a temperature of 66 ° 
Fah. being about 62*3 lbs., that the total weight of water deliv¬ 
ered per hour was 161‘2 x 62*3 = 10,042’76 lbs., so that the total 
amount of heat imparted to the water per hour was 10,042*76 X 
84 = 843,591*84 units. 

The total heat above 32° in a pound of dry steam, at a pressure 
of 130 lbs. per square inch, is 1187*8 units, and the heat remain¬ 
ing in a pound of steam above 32°, after condensation, is 150 
— 32 = 118 units, so that each pound of dry steam imparted 
1187*8 —118 = 1069*8 units of heat to the feed-water, and the 

. , _ 843,591*84 r700 />11 

weight of dry steam required per hour was i069 v 8 — = lbs * 

The height of a column of water equivalent to the pressure against 

which the water was delivered was — ^.g" ~— ~ 300*5 feet, so that 

the useful work performed per hour was 10,042*76 x 300*5 = 
3,017,049*38 foot-pounds. The weight of coal required to do this 

788*6 

work, on the assumed boiler evaporation, was —— 37*6 lbs., 

so that the duty of the injector, per 100 lbs. of coal, was 
3,017,049-38 x 100 _ 3 455 535 foot-pounds. 


87-6 






416 


/ 


THE ENGINEER’S HANDY-BOOK. 


The term range is frequently used in connection with injectors, 
and means the difference between the maximum and minimum 
delivery. 

TABLE 

SHOWING THE MAXIMUM AND MINIMUM DELIVERY OF SELLERS’ SELF- 
ADJUSTING, 1876 , INJECTOR NO. 6 ; TEMPERATURE OF DELIVERED 
WATER ; PRESSURE AGAINST WHICH INJECTOR DELIVERS WATER, AND 
HIGHEST TEMPERATURE OF FEED ADMISSIBLE ; WATER FLOWING TO 
INJECTOR UNDER 15 INCHES HEAD ; WASTE-VALVES SHUT. 


Pressure of Steam Supplied to 
Injector, and Pressure against 
which Water is Delivered. 

Lbs. per Sq. In. 

Delivery in Cubic 
Feet Per Hour. 

Temperature Fahren¬ 
heit Degrees. 

Pressure of Steam Required to 

Deliver Water against Press¬ 

ure in Column 1. 

Highest Temperature admissible 

of Feed-Water, Fahrenheit 

Degrees. 

• 

Maximum. 

Minimum. 

Ratio of Minimum to 
Maximum Delivery. 

Feed-Water. 

Delivered 

Water. 

At 

Maximum Delivery. 

At 

Minimum Delivery 

1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

75*3 

63*6 

0*845 

66 

100 

94 

3 

132 

20 

82*4 

61*2 

0*743 

66 

108 

104 

9 

134 

30 

94-2 

56*5 

0*600 

66 

114 

116 

16 

134 

40 

100 * 1 

60*0 

0*599 

66 

120 

123 

22 

132 

50 

108*3 

64*7 

0*597 

66 

124 

125 

27 

131 

60 

116*5 

63*6 

0*546 

66 

127 

133 

34 

130 

70 

124*8 

63*6 

0*510 

67 

130 

142 

40 

130 

80 

133*0 

67*1 

0*505 

66 

134 

144 

46 

131 

90 

141*3 

69*5 

0*492 

67 

136 

148 

52 

132 

100 

147*2 

64*7 

0*456 

66 

140 

159 

58 

132 

110 

153*0 

67*1 

0*439 

67 

144 

162 

63 

132 

120 

156*6 

73*0 

0*466 

67 

148 

162 

69 

134 

130 

161*2 

74*2 

0*460 

66 

150 

165 

75 

130 

140 

166*0 

78*9 

0*476 

66 

153 

166 

81 

126 

150 

170*7 

70*6 

0*414 

66 

157 

167 

88 

121 


The table of capacities shows the maximum delivery, but the 
injector can be regulated so as to reduce the amount about 60 per 
cent. 



































THE ENGINEER S HANDY-BOOK. 


417 


H 

P 

W 

<1 

Eh 


w 

« 

o 

H 

a 

w 

>-5 


02 

Z 

w 

l-i 

Hi 

w 

02 

Pm 

O 

w 

W 


O 

p* 

o 

Pm 

O 


m 

C 

s 

o 

Pi 


a 

ci 

<33 

CO 

Vh 

o 

4) 


03 

03 

03 

- 

Ph 


o 

o 


o 

05 


o 

00 


o 

1- 


o 

CO 


© 

to 


o 

rH 


o 

co 


o 

04 


H 

3 

o 

« 

(h 

03 

PM 

'O 

03 

tc 

H 

CS 

F-» 

a 

co 


Jh 

<D 

- 4 -J 

c3 

> 


<u 

<v 

Pm 

o 

•rH 

.o 

r-' 

o 


<X> I 
o, O 

•£7 <x> 
pH f=! «5 
fl C3 

"a-B 
J § 

CO Ml 


I 

a 

~ u 

o 

03 03 

N ■—> 

ss 


PI CO N 1(5 a; Os OS -H 04 O0 
CDO4l^00tatOrHto-HrH©00rHO4 
• ••••••••••••• 

Hccoo^oocoHaHOTtto 

HritMPlIC'^'OXOCCO 


CO CO ^ IO CO rH CO rH CO (01 
OSTt < iOOS'1'QOOrfup32HlO>OH 

COCOnOOHHQOCONHOOSO 
1 —I ©0 CO 05 rf OS lO r-IOSON hiMZ) 
HHOlCOCOtONOOHO 


© rH 04 CO 00 I" 00 00 © 

04 CD rH O 00 rH CO 04 IQ 00 rH C4 tO OS 

CO rH 00 04 CO 04 00 04 CO 00 rH OS rf OS 

t—ICO tOOSCOODCOCNCOCOlOr(OS 
Hrl 04 CO CO tO © Ol rH 


OS 

tO 00 CO ■ 


rH 00 

04 CO 


CO 


CD 


00 

Ol 


H+l 

CD 00 


040StOt— CDO-lcDCDCOOrHOOOSOS 
rH04»0C004t'(M00t0rHDO^H 
rHrH0404C0t0©©r-HrH 


04 CD 00 OS tO t-Hfi t^04r- 
00 rH rH rH O CD 04 OS CD 04 04 t" 1" 


-H 

CD 


00 04 C4C5 04 C005COrHi-H©rHC5 
O4tO0Cr— CD rH 0 M 00 to to 00 CO 
rirH(M04MTfC0 00 OC0 


tO 04 CD l'- CO 04 00 04 rH 00 00 

coocicsa^oOD^co^i'^ 

CDOSNrHClbcOCOOliHlbcsO 
04 rH 1— rH lO ©> tO rH lO rn O t—h lO 
rtHP|04CO^CDC0004 


00 00 rH rH CD 04 CD CD CD 04 

THlO00C000O4©©tr©C0rH00C0 

o-^*bo4’^fcoi^t-cocoAH'-t | '0 < cs 
rH 04 rH O rH 00 CO OS 04 N 00 to 4- 
rH rH rH 0-4 04 rH lO l'* CS rH 


rH "H* 04 04 00 rH CD r-H 00 CO CD 

tr 00 I- rH lr rH 00 to t- 00 rH OO CS rH 

CS 04 04 l*~ CO rH Ah CO rH rH 04 CS CS 

04 rH CD CS CO t- 04 1" CS CO O 00 CS 

rH rH 04 04 CO tO 1— 00 ©> 


rH tO LO tO 

05 O CD tO CO 1 ^ co 00 . rH © 

rH OS (04 © CO 04 tO M ® A H lb CS 

04C0CDCS<01CDOt0CDCSi0 01rH 

HH 04 04 C 0 ^C 00 O 


t'- CD 00 00 CO rH © 04 i> rH 

C 004 ©tOrH©C 4040 C 04 rHCO ©00 

00 05 © l"— CO rH OS D CO l> H O C 00 
HCOiOOOr’tCOCOCOiOOCDCO 
rH rH rH <04 CO rH CD l" CS 


iHlNWhH r'r *—ir h£-i h!mh|m rici 

r*H rH rH rH 04 04 04 04 04 CO CO CO 


04 CO ^ tO CD N CO CS O P4 ’■f D 00 O 
rH rH rH rn rH 04 

O ^ V# 


W 

H 


Q 

H 

W 

E^h 

Ph 

O 

W 

pH 

p 

H 

< 

P5 

W 

Ph 

S 

H 


◄ 

w 

Eh 

in 

Pm 

O 

cn 
W 
Ph 
to 
02 
cc 
W 

Ph 

Ph 

Eh 

!Z 

W 

Pi 

w 

Pm 

Pm 


Eh 

< 

w 

1-1 

w 

I—I 

C/2 

C/3 


Q 

<1 

« 

Pi 


0 

H 

Ph 

Ph 

Pm 

O 

w 

Pi 

to 

Eh 

■< 

Pi 

Pi 

Ph 

HH 

r". 

Pi 

Eh 

i —i 

P 


<1 


o 

o o 

© rH 


o 

o o 

to 04 


o 

© rH 
rH 04 


o 

O O 
CO CO 


o 

O ao 
04 co 


o 

O 00 

rn rH 


O 

c 

hh © 

H3 « 

Mh — 

a c 

S 03 

cr {: 

llJ 

o-u 

cc 03 

os t; 

WW 

ii 

Ph a! 
SPh 

I o 

CO <u 

M— ^ 

O B 

03 

Mh *r 

r 03 


£ es 

U 03 

Ph H 


2 B 


















































418 


THE ENGINEER’S HANDY-BOOK. 

The reputation of the Sellers’ injectors stands deservedly high 
for efficiency, reliability, and action. They are adapted to all pur¬ 
poses for which such instruments are employed, such as boiler- 
feeders for steamships, locomotives, and stationary engines. Every 
injector is tested at the works by being attached to a steam-boiler 
before being sent out, and tried under different pressures, which 
insures entire satisfaction in the working, so that it is sure to meet 
all the requirements for which it is intended. 


Rue’s “ Little Giant” Injector. 

The annexed cut represents Rue’s “Little Giant” Injector, class 
A, which, as a boiler-feeder, has a reputation for simplicity, efficien¬ 
cy, and capacity second 
to no other in the coun¬ 
try. All that is neces¬ 
sary to be done in order 
to start it, is to turn on 
the water, and, when it 
flows from the overflow, 
turn on the steam, slowly 
at first, until it reaches 
the water, then turn on 
full head, and push the 
lever M slowly, either 
forwards or backwards, as seems requisite, until neither steam nor 
water shows at the overflow. When it is ascertained where the 
lever must be set, for the steam carried, it can be adjusted before 
beginning, or left as it is, when steam is shut off. The lever is 
only used to regulate the proportionate amounts of steam and 
water. The injector will feed one-half its capacity, by decreasing 
the amount of steam, and then adjusting the lever. By a little 
practice, any engineer can adjust it, so as to feed a steady stream 
of exactly the amount necessary for use. 























THE ENGINEER’S HANDY-BOOK. 


419 


To set up Class A. — Place the injector in a horizontal position, 
at any convenient point, so that the pipes will be as short and 
straight as possible. Place an ordinary globe-valve on the steam- 
pipe ; attach the steam-pipe to the swivel marked steam, and the 
water-pipe to that marked water; place a valve or stop-cock on 
the same, as near the injector as practicable. If the water-sup¬ 
ply is from a tank, let the fall be as great as possible, but if 
from a hydrant, or any other source having a pressure which is 
not regular, as is frequently the case, let the water-pipe be one size 
larger than the swivel, and attach it to the latter by a reducer. 
Attach the delivery-pipe to the swivel marked — “ to boiler.” 

The following cut represents the “ Little Giant” Lifting Injec¬ 
tor, class B, which is used for locomotives and steamships, and will 
lift water 12 feet at 40 
lbs. pressure. This in¬ 
jector, whether used on a 
locomotive or steamship, 
should be conveniently 
located to the engineer. 

The method of working 
it is identical with that 
of class A, except that 
the steam-jet valve should 
be first opened, then the 
water turned on, and, 
when it appears at the 
overflow, the main steam supply-valve should be opened gradually 
until it catches the water, when it may be turned on full head. 
The steam for them should be taken from the highest point in 
the boiler, so that it may be dry and elastic. Great care should 
be taken to see that the water-pipes are all perfectly tight. No 
washers should be used on the swivels by which the steam- and 
water-supply pipes are attached to the injector. If there are any 
floating particles, such as sawdust, shavings, straw, bran, or chaff, 



























420 


THE ENGINEER’S HANDY-BOOK. 


in the water, the end of the pipe should be covered with a wire- 
strainer. 

To start the lifting injector, Class B, open the jet-valve until 
water shows at the overflow in a solid stream; then turn on the 
steam as before, and, when the water is entering the boiler, shut 
the jet. Great care should be taken to see that the supply-pipe, 
through which the water is lifted, is perfectly air-tight, as auy 
leak in the pipe will interfere with the working of the injector. 
When water is to be lifted by this injector, a small steam-pipe 
leading from the boiler, and furnished with a valve that opens 
with a quick motion, is attached to the swivel, P, by means of 
which a steam-jet is thrown into the tube, P, and the water lifted. 


TABLE 

OF CAPACITIES OF RUE’S “ RITTLE GIANT” INJECTOR. 


Size of 
Injectors. 

Size of 
Pipe Con¬ 
nections. 

Pressure 
of Steam 
in Pounds. 

Gallons 
per Hour. 

Nominal 

Horse- 

Power. 

0 


90 

60 

4 

to 

8 

1 

1 

90 

90 

6 

ii 

•12 

2 

* 

90 

120 

8 

u 

20 

3 

a 

4 

90 

300 

20 

tt 

40 

4 

1 

90 

600 

40 

tt 

80 

5 

a 

90 

900 

60 

tc 

120 

6 

a 

90 

1200 

80 

tt 

160 

7 

a 

90 

1620 

140 

tt 

225 

8 

2 

90 

2040 

200 

tt 

275 

9 

2 

90 

2480 

250 

tt 

350 

10 

2 

90 

3000 

300 

tt 

400 

12 

21 

90 

3600 

350 

tt 

500 


Friedman’s Injector. 

♦ 

The annexed cuts represent the Friedman Injector, which 

is adapted to a great variety of purposes, such as raising water 

















THE ENGINEER’S HANDY-BOOK. 


421 




or other fluids from tanks, wells, mines, quarries, cellars, docks, the 
holds of vessels, etc. They have also been successfully employed 
in breweries, distilleries, chemical works, and sugar refineries, for 
conveying acids, fluids, or liquids from tank to tank, or from 
one room to another. In general appearance the injector is of 
cylindrical form, with 
three openings, as in all 
others ; one of each for 
the suction, steam, and 
delivery. As will be ob¬ 
served, as in all other in¬ 
jectors, instead of one 
nozzle or cone there are 
a series in this injector; in this arrangement lies the secret of its 
capacity and utility. 

As the steam-jet acts at first only on that portion of the in¬ 
coming water which is admitted through the first nozzle, or cone, 
so that only a comparatively small jet of steam is required to 
move it, this stream, 
propelled by the 
force of the steam, 
gives an impetus to 
the water entering 
through the second 
cone, and that in 
turn becomes a mo¬ 
tor to the next, and so on until the last is reached. The water 
or liquid accelerated in its passage through these successive noz¬ 
zles or cones, as well by the force already described as by the 
vacuum always formed under such conditions, is carried with great 
velocity through the diverging-pipe into the discharge-pipe, with 
all the force and rapidity necessary to convey it to its required 


Section of Friedman’s Injector. 


destination. 


36 


j 



























422 


THE ENGINEER^ HANDY-BOOK. 


TABLE 


OF CAPACITIES OF FRIEDMAN’S INJECTORS. 


Size of 
Injec¬ 
tor. 

Minimum 
Inside 
Diame¬ 
ter of 
Pipe in 
Inches. 

Delivery per Hour, in Gallons, at a Steam- 
Pressure of 

120 lbs. 

80 lbs. 

50 lbs. 

20 lbs. 

No. 2 

2 

90 

80 

63 

39 

“ 3 

t 

220 

180 

141 

90 

“ 4 

1 

390 

320 

243 

160 

“ 5 

u 

630 

500 

395 

250 

“ 6 

u 

870 

720 

570 

360 

“ 7 

n 

1200 

965 

774 

500 

“ 8 

u 

1560 

1280 

910 

639 

“ 9 

2 

1980 

1620 

1380 

810 

“ 10 

2 

2450 - 

2000 

1580 

990 

“ 12 

21 

2870 

2880 

2275 

1440 



The Keystone Injector. 

The above cut represents the Keystone Injector, class A, 
which is used for feeding boilers where the water-supply is re¬ 
ceived from street-mains, reservoirs, cisterns, etc. It should be 






















































THE ENGINEER’S HANDY-BOOK. 


423 


placed in a horizontal position, and, if the water is taken from a 
tank, the injector should be below the supply. All connections, 
whether for steam or water, should be of the same internal bore 
as the nipples on the injector. The steam should be taken from 
the highest part of the boiler, in order that it may be dry, and the 
pipes should be as short and straight as possible, and should not 
be connected with any supply-pipe or feeder employed for any 
other purpose. A globe-valve should be placed on both the steam- 
and water-pipes, but no extra check-valve is necessary, except the 
one in the swivel, which controls the outlet to the boiler; nor is 
any washer or packing necessary for any part of the injector or 
its connections, as all of its joints are ground. 

To start the injector. — Open the steam-valve for the purpose 
of allowing any water resulting from the condensation of steam 
to escape; then close it; next open the water-cock, then the steam- 
valve, and move the plug B slowly forward by means of the 
handle b, until the water ceases to appear at the overflow. And 
if, while the injector is working, water should commence to run 
from the overflow, move the plug slowly forward until the water 
ceases to flow. If steam escapes, move the plug backward for the 
purpose of giving the injector more water. When the lever b is 
set, so that the injector works dry, all that is necessary to do to 
stop its feeding is to close the steam-valve first, then the water- 
valve ; and, when it becomes necessary to feed again, the injector 
may be started by first opening the water-cock and then the steam- 
valve. The lever being only used to regulate the volume of steam- 
and water-supply, if the lever moves too loosely, it may be tightened 
by screwing down the nut on the spindle C ; if too tight, the nut can 
be slacked up. This injector will work under ordinary circumstances, 
but there are other injectors in the market which are immensely 
superior to them. 

The Keystone Lifting Injector. 

The cut on page 424 represents the Keystone Lifting Injector, 
class B. The same instructions for setting up and manipulating 
class A, Fig. 1, apply to this also, with this exception, that no stop- 


424 


THE ENGINEER’S HANDY-BOOK. 


cock or valve is necessary on the water-supply. The jet D serves 
to create a vacuum, and assists in carrying the water forward 
against the boiler-pressure; and, as it is stationary, it is always in 
a proper position to produce a vacuum, the required volume of 
steam necessary to force the water into the boiler being obtained 



by moving the plug B, as in the case of class A. To lift water 
from a well, open the steam-valve for the purpose of removing 
the water of condensation; then close it; after which move the 
plug B back against the disc of the jet D ; then open the steam- 
valve, and, when the water appears at the overflow, move the plug 
slowly forward until the water ceases flowing, after which the in¬ 
jector will sometimes lift water, but are said not to be reliable as 
lifting injectors. 

The Eclipse Injector. 

The cut on page 425 represents the Eclipse Injector, with Sellers’ 
Lifting Jet, which is claimed to embody many desirable features, 
such as simplicity, durability, and easy adjustment, and to work 
under a steam-pressure ranging from 5 to 150 lbs. per square inch, 
without breaking the water-supply; that, when it becomes neces¬ 
sary to fill a boiler with cold water, all the working parts may be 
removed from the barrel, which will permit the water to flow 
through without obstruction ; that it will heat the feed-water up 






































THE ENGINEER’S HANDY-BOOK. 


425 


to 200° Fall.; and that it is particularly adapted to heating the 
water in the tenders of locomotives, to prevent them from freezing. 

The same precautions that are necessary to be observed in con¬ 
necting all injectors, viz., that the steam be taken from the high¬ 
est point of the boiler; that a valve must be placed in the steam- 
pipe near the swivel, and also one on the feed-pipe between the 
boiler and check-valve ; and that the water connections are per¬ 
fectly tight, are applicable to this one, also. 

Directions for using the Eclipse Injector. — Close the regulator, 
A, by turning it to the right as far as it will move; then turn on 
the steam, slowly at first, until the water which is taken up shows 
at the overflow; next open the regulator slowly, until the dis¬ 



charge from the overflow ceases; the injector will then be working. 
When it becomes necessary to stop working, first turn oft the 
steam; then close the regulator, as otherwise, when started again, 
it will not lift quickly; but, when the water flows to the injector 
from either a hydrant or tank, after the injector has once been 
adjusted, it is only necessary to turn on the water, and then the 
steam. To remove the working parts from the barrel of the in¬ 
jector, screw the jam-nut, C, up against the main nut, D ; then, by 
keeping the jam-nut tight against D , the injector may be easily 
drawn out from the shell. Should it become necessary to repack 
the injector at M, care must be taken to insert the packing in 
front of the follower, T, and compress it with the latter. 

36* 

















































426 


THE ENGINEER^ HANDY-BOOK. 


The Clipper Injector. 



The annexed cut represents the Clipper Adjustable Injector, 
which is claimed to possess the following good qualities : simplicity 
of construction, certainty of action, ease of starting, non-liability to 

get out of order, large capacity, and 
that it will draw water as far as a 
siphon or pump, and force it into 
the boiler under ordinary pressure. 
Besides, it can be regulated so as to 
feed one-half its capacity, and will 
not slip. ) 

All that is necessary to insure 
certainty of action in this injector, 
is to place it in a horizontal position, 
and take the steam from the highest 
point in the boiler, and to have the 
steam- and water-pipes fully as large 
as the openings in the swivels to 
which they are attached. 

The cut on page 427 shows a sec¬ 
tion of Lynde Clipper Injector. —A 
is the shell or body; B, the steam- 
tube; C, the jet or lifting-tube; D, 
the water-tube; H, the swivel which 
is kept from turning by the fins H; 
K , the bonnet, by unscrewing which 
the tubes B and C may be re¬ 
moved ; M and N, revolving lever 
and handle by which to regulate the 
water and steam ; 0, overflow holes; 
O', holes to assist in lifting, on starting the injector; Q, strainer 
to prevent any foreign substances from entering the injector with 
the water; B, ribs to prevent the shell from springing; W, over¬ 
flow valve and spring. 




















THE ENGINEER’S HANDY-BOOK. 


427 


Draw the 


How to start the injector when the water flows to it. 
steam-tube, 1B, nearly all the way 
back, by revolving the handle, if, 
which actuates tube, B (same as the 
wheel does the valve in a common 
globe-valve), and pull lever, if', all 
the way back. Open steam-valve 
a little, to clear pipe of condensed 
water; when steam blows out at 
overflow, push lever, if', full for¬ 
ward, open steam full, and open 
water-cock. When water runs solid 
from overflow, draw lever, if', 
slowly all the way back, and turn 
in tube, B, slowly till water ceases. 

The injector is then set to feed its 
maximum amount at the pressure 
of steam then used. It may then 
be started by simply opening steam- 
valve a little, as above, to clear the 
pipes; then close steam- and open 
water-cocks. When water runs 
solid at overflow, open steam-valve 
slowly, and feeding will commence 
without operating lever, if'. 

How to start the injector when 
the water is to be lifted. —Draw 
steam-tube, B, nearly all the way 
back, and pull lever, if', all the 

way back; open steam-valve a little (or all the way, if desired), 
to clear steam-pipe, and, when steam appears at overflow, push 
lever, if', full forward — the water-pipe being open, water will 
be likely to appear at once (or in a few seconds) at overflow; if 
not, pull lever, if', back a moment to clear the injector and push 
full forward again. As soon as the water runs solid at overflow, 



TO BOILER 

























































428 the engineer’s handy-book. 

pull lever, M ', slowly all the way back, and screw in tube, B, until 
feeding commences. It is then feeding the maximum amount at 
pressure. It may then be started by turning on steam ; push lever, 
full forward, and then pull back as above, when water appears 
at overflow. 

To reduce the feed in either case. — When the injector is set 
as above, push lever, M', forward, until water begins to run from 
overflow; then cut off water with handle, M , until it ceases at 
overflow, and repeat as long as it will bear, and continue to feed. 
The minimum feed is thus obtained, and the water is delivered to 
the boiler the hottest. 

TABLE 


OF CAPACITIES OF CLIPPER INJECTORS. 



Pipes. 

Approximate Gallons 

No. 



of Water thrown per 



Hour, with 60 to 100 


steam. 

WATER. 

Lbs. of Steam. 

1 

1 in. 

1 in. 

■4 

60 to 90 

2 

3 (t 

8 

1 “ 

150 to 180 

3 

1 “ 

3 U 

4 

250 to 300 

4 

a. « 

4 

1 “ 

500 to 600 

5 

1 “ 


700 to 900 

6 

1 “ 

11 “ 

800 to 1200 

7 

11 “ 

a “ 

1200 to 1600 

8 

a “ 

a “ 

1600 to 2000 

9 

a “ 

2 “ 

2000 to 2500 

10 

a “ 

2 “ 

2500 to 3000 

12 

2 “ 

21 “ 

3000 to 3500 


There is one principle that governs the action of all injectors, 
which is, that if the temperature of the water is raised too high, 
they will not work. Some injectors will lift water as high as 20 
feet, according to the temperature of the water and the size of the 
injector; large injectors having invariably the greatest lifting ca¬ 
pacity. As the amount of water thrown depends on the velocity 











THE ENGINEER’S HANDY-BOOK. 


429 


of the steam, it follows that the volume of water thrown will be 
much greater with high than with low steam-pressure. 

The annexed cut represents Mack’s Fixed-Nozzle Injector, 
which is said to have a working range, with one handle, of from 
15 lbs. to 175 lbs. steam-pressure per square inch, and is always 
reliable, whether worked con¬ 
stantly or once in a year. 

When extraordinarily high 
pressure is required, an ex¬ 
tra valve is attached, which 
will admit of working this 
injector at a range of 5 lbs. 
to 250 lbs. per square inch. 

Fixed - Nozzle Injectors 
have no movable or adjust¬ 
able parts within them; they 
can be regulated by steam- and 
water-supply cocks on the 
outside of the instruments; 
but there is one pressure of 
steam to which they have 
been primarily adapted, and 
at which they work best, viz., 
at the pressure at which they 
give the largest duty. Inas¬ 
much as the pressure of steam 
in stationary boilers is, as a 
rule, held constant, they are 
well suited for that kind of 
work; but in cases where there 
is a great variation of press¬ 
ure they are not so well suited. Mack’s Fixed-Nozzle Injector. 

There are fewer of them in use than of other arrangements, never¬ 
theless some of them give satisfaction, but in any case their sim¬ 
plicity is their chief recommendation. 
















430 


THE ENGINEER^ HANDY-BOOK. 


The Inspirator. 

The inspirator, though belonging to the injector family, differs 
from the latter, inasmuch as it is a double instrument, consisting 

of a lifting and a forcing 
side; the latter being to all 
intents and purposes, with 
slight mechanical varia¬ 
tions, an “ injector,” while 
the former is a kind of a 
pump, which supplies the 
forcer side with water. 
The whole machine is a 
curious combination of 
mechanical arrangements 
for lifting and forcing 
water, and cannot be act¬ 
ually said to be either an 
injector or a pump, though 
it performs the functions 
of both. The inspirator 
is capable of lifting and 
forcing water or other 
fluids to a great height. 
It will lift water 25 feet, 
with a steam-pressure of 
30 lbs., provided the suc¬ 
tion-pipe be perfectly tight, 
and the instrument is fur¬ 
nished with dry steam; but 
the temperature of the 
water will control to a 
certain extent the height 
of the lift. For a lift of 25 feet, the temperature of the water 
should not exceed 100° Fah. 





































































































































































































































































THE ENGINEER’S HANDY-BOOK. 


431 



STEAM 


Whenever the inspirator fails to act, the trouble, in a majority 
of cases, will be due to leakage in the pipes. Other causes are due 
to the area of the suction- 
pipe being too small, which 
ought in all cases to be 
larger than the nipple or 
swivel to which it is con¬ 
nected ; but in any case it is 
advisable to have a foot-or 
check-valve in the suction- 
pipe, below the level of the 
water in the well, river, or 
mine. 

How to operate the in¬ 
spirator. — When steam is 
admitted to the inspirator, 
it passes through the lifter 
steam-jet, leaps the interval, 

A, through the combining- 
tube, and escapes at the over¬ 
flow, thus expelling the air 
and producing a partial 
vacuum, into which the 
water rises. As soon as the 
water appears at the over¬ 
flow, close valve No. 1, to 
prevent it from escaping, 
and induce it to pass up the 
forcer, and through the com¬ 
bining-tube B; then by open¬ 
ing the handle No. 2, and closing No. 3, the water is forced 
directly through the feed- or delivery-pipe into the boiler or tank, 
as the case may be. The inspirator is adapted as a boiler-feeder 
for either stationary, locomotive, or marine engines. 


OVERFLOW. 

















































432 


THE ENGINEER’S HANDY-BOOK. 


TABLE 

OF CAPACITIES OF THE HANCOCK INSPIRATOR. 


Number of Inspi¬ 
rator. 

Size of Pipe Con¬ 
nections. 

Gallons per Hour. 

10 

4 

120 

15 

2 . 

4 

320 

20 

1 

540 

25 

H 

900 

30 

1! 

1260 

35 

H 

1540 

40 

2 

2240 

45 

2 

2820 

50 

2i 

3480 


Instructions for Setting up, Properly Attaching, and 

Adjusting Injectors. 

All pipes, whether steam, water-supply, or delivery, should be 
of the same internal diameter as the hole in the corresponding 
branch of the injector, and as short and straight as practicable. 

When floating particles of wood, or other matter, are liable to 
be in the supply-pipe, a strainer should be placed over the receiv¬ 
ing end of it. The holes in this strainer should be as small as the 
smallest opening in the delivery-tube, and the total area of all 
the holes should be greater than the area of the water-supply pipe, 
to compensate for the closing of some of them by deposits. 

The steam should be taken from the highest part of the boiler, 
in order to avoid the carrying over of water with the steam; but 
it should not be taken from the pipe leading to the engine, unless 
such pipe is large. 

When any injector capable of raising water is set, care must be 
taken to have the pipes as tight as possible, so as not to draw 
air. 


» 








THE ENGINEER’S HANDY-BOOK. 


433 


If the water is not lifted by the injector, but flows to it from a 
tank or hydrant, there should be a cock in the water-supply pipe; 
and in case the injector be self-adjusting, this cock should be of a 
kind that will prevent any considerable pressure in the water- 
supply pipe between it and the injector. The higher the steam 
is carried in the boiler, the greater may be the pressure in the 
water-supply pipe. 

There should always be a stop-valve or cock in the steam-pipe, 
between the steam-space in the boiler and the injector, and a 
check-valve between the water-space of the boiler and the in¬ 
jector. 

When an air-chamber is placed below the injector in the water- 
supply pipe, care should be taken to keep it supplied with air. 
When the injector lifts water from a tank placed below it, no pre¬ 
caution is needed, as, when the injector is stopped, the water flows 
back and air enters the pipe. 

When fed from a hydrant through a self-regulating valve, there 
should be a pet-cock between the valve and the air-chamber, 
which will serve to drain away the water when the valve is closed 
and the injector is not working. 

After all the pipes are properly connected to the injector and to 
the boiler, and it is ready for work, they should be disconnected 
and well washed out, in order to remove any obstructions, such as 
paint, red lead, straw, or shavings, that may have found their way 
into them. Many excellent instruments have been condemned 
because those who set them up failed to take this precaution. 

Injectors, like pumps and other hydraulic machines, are not so 
reliable in action when working water of a high temperature as 
when the temperature is moderate; though there are several in¬ 
jectors, owing to peculiarities in their mechanical arrangements, 
more reliable in this respect than others. 

Injectors, like nearly all other machines connected with steam- 
boilers, are frequently neglected, and allowed to become covered 
with filth, which, in view of their wonderful utility and efficiency, 
is a reproach to those who have them in charge. 

37 2 0 


434 


THE ENGINEER^ HANDY-BOOK. 


STEAM 


The Ejector or Lifter. 

The annexed cut represents the ejector or lifter, which is prac¬ 
tically the lifter side of the inspirator, with a reduced steam-jet 
and enlarged lifter combining-tube. It is suitable for breweries, 

tanneries, bleacheries, etc.; for trans¬ 
ferring large volumes of water, lye, acid, 
and other liquids. It will deliver more 
fluid of any kind at a low lift, with a 
lower pressure of steam, than either the 
injector or inspirator; but it is not as 
reliable, or as well adapted to the dif¬ 
ferent purposes for which these instru¬ 
ments are used, as either of them. It 
answers a very good purpose when cellars 
become flooded in consequence of heavy 
rain-falls, high tides, or overflowing of 
culverts, and requires no very intelligent 
management. Its action is based ou the 
[DELIVERY same principle as that of the injector, 
and is more simple, as it has no adjust¬ 
able or movable parts. 

Method of starting the ejector. —All 
that is necessary to start the ejector is to 
turn on the steam, after which it will 
work as long as the water-supply and 
steam-pressure continue; and it is imma¬ 
terial what lift it is started on, as the 
steam-supply may be gradually reduced 
to meet the requirements of the quantity of water to be dis¬ 
charged. If started on a steam-pressure of 40 lbs. per square 
inch, it will continue to work until the pressure falls to 15 
pounds. 

The Ejector and Inspirator are manufactured by the Hancock 
Inspirator Co., Boston, Mass. 



SUCTION 






















































THE ENGINEER’S HANDY-BOOK. 


435 


Jamison’s Steam Water-Ejector. 


The annexed cut represents Jamison’s steam water-ejector, 
as it is termed, which, like other eject¬ 
ors, is suitable in tanneries, breweries, 
or places where large quantities of liq¬ 
uids which contain floating particles, 
such as malt, hops, bark, sawdust, etc., 
require to be lifted, as it has no moving 
mechanism to be obstructed or clogged. 

Its action is based on the same prin¬ 
ciple as the steam siphon, and when 
once started, by simply turning on the 
steam, it will continue to work as long 
as the steam and water-supply lasts, 
through a diminution of pressure rang¬ 
ing from 15 to 100 lbs. per square inch, 
and vice versa. As they are generally 
made of brass or some non-corrosive 
metal, they rarely ever wear out or 
require any attention. They are just 
as efficient when submerged in water 
or other liquid as when directly on 
the surface. 

TABLE 



OF CAPACITIES OF JAMISON’S STEAM WATER-EJECTOR. 
SIZE. CAPACITY. 


3 

8 

inch 

ejector. 

4 gals. 

per minute 

1 

2 

U 

(< 

8 

u 

a 

<« 

3 

4 

u 

a 

12 

a 

« 

«( 

1 

u 

a 

15 

u 

(( 

M 

H 

iC 

a 

20 

<( 

u 

a 

n 

u 

u 

30 

« 

<t 

« 

2 

a 

u 

80 

u 

(( 

« 

3 

u 

<« 

300 

(( 

tc 

it 




















































436 


THE ENGINEER’S II ANDY-BO OK. 


Questions, 

THE ANSWERS TO WHICH WILL BE FOUND IN THE TEXT. 

What is the object of attaching a condenser to a steam-engine? 

Give the names, and the advantages and disadvantages of the 
two kinds of condensers in most general-use, with a description 
of the same. 

Explain how the injection-water enters and escapes from surface 
and jet condensers. 

State what relative proportion the jet condenser should bear to 

the steam-cylinder of a condensing engine. 

State what relative proportion the cooling surface in a surface 
condenser should bear to the cubic contents of the steam-cyl-. 
inder. 

State the respective advantages and disadvantages of having 
condensers too large or too small. 

What is the most advantageous temperature at which to keep 
the water in hot wells? and what effect does too high or too low a 
temperature exert on the economical working of the engine? 

Explain the arrangements by which the bilge injection-water is 
introduced into jet and surface condensers. 

What would be the effect of not shutting off the injection-water 
when the engine is stopped? 

State the quantity of water necessary to condense steam, with 
a formula. 

Give the rule for finding the cooling surface in the tubes of sur¬ 
face condensers. 


THE ENGINEER’S HANDY-JiOOK. 437 

What is the most practicable method of cleaning the tubes of 

surface condensers when they become foul ? 

State what relative proportions the circulating-pump should 
bear to the steam-cylinder of a surface-condensing engine. 

Explain the principles involved in the working of the Korting 
jet condenser; also the method of starting it. 

What is the meaning of the term vacuum? 

How is the vacuum maintained in the condenser of a condens¬ 
ing engine? 

What effect has the temperature of the injection-water on the 
vacuum ? 

How is the vacuum measured ? 

Suppose the steam-gauge shows 60 lbs. pressure, and the 
vacuum-gauge registers 26 inches, what will be the effective press¬ 
ure on the piston ? 

Why does the condensation of steam produce a vacuum in the 
condenser ? 

How is the state of the vacuum shown? 

From what causes is an imperfect vacuum most likely to arise? 

How would you proceed to discover the cause of an imperfect 
vacuum ? 

Is a vacuum power? 

Can a perfect vacuum be maintained ? If not, why not? 

What is the object of air-pumps used in connection with con¬ 
densing engines ? 

What relative proportion should the air-pump bear to the steam- 
cylinders of simple and compound surface-condensing engines? 

37* 


438 the engineer’s handy-book. 

What relative proportions should the air-pump bear to the 
steam-cylinders of jet-condensing engines ? 

What is the difference in the duty which the air-pumps of sur¬ 
face-condensing and jet-condensing engines have to perform? 

Explain the difference between bucket, piston, plunger, single 
and double acting air-pumps. 

What is the object of attaching an air-valve to a circulating, 
reciprocating, or double acting pump ? 

What is the most probable cause of an air-pump with a foul 
valve, and no discharge-valve, failing to work ? 

What is the object of an air-pump trunk? 

What are the functions of an air-pump pet-cock? 

Describe the construction of an air-pump bucket. 

With what metals are air-pump rods generally covered, and 
why are they so covered ? 

Give the shape and functions of a ship’s side air-pump discharge- 
valve. 

What is the object of an air-casing? 

What is the object of the mariner’s compass ? 

What are the causes of variation of the compass? 

What is the meaning of the term rhumbs? 

What is the equator? 

What are the poles ? 

What is a meridian ? 


THE ENGINEER’S HANDY-BOOK. 439 

What is the meaning of the term latitude? 

What is understood by difference of latitude? 

What is the meaning of the term departure in its relation to 
navigation ? 

What is the meaning of the term longitude? 

What are degrees of longitude? 

Give the rule for reducing degrees of longitude to time. 

What is the difference of longitude between any two places? 

Define the term distance in its relation to navigation. 

Define the terms course and magnetic course as applied to 
navigation ; also the terms true course and course made good. 

Define the terms variation, deviation, and error of the compass. 

Define the term leeway. 

Define the terms meridian; and also apparent, observed, and 
true altitude. 

Explain the term visible horizon and dip of the horizon. 

What is the meaning of the term refraction? 

Give the meaning of the term port side. 

What is the parallax? 

What is the meaning of the term declination? 

/ 

What is meant by polar distance ? 

What is meant by right ascension? 

What is meant by semi-diameter? 



440 


THE ENGINEER’S HANDY-BOOK. 

Give the meaning of the term starboard side. 

What is meant by the augmentation of the moon’s semi-diameter ? 

What is the zenith distance? 

Explain the terms civil, astronomical, sidereal, apparent, and 
mean time; also the equation of time. 

What is meant by the hour-angle of a celestial object? 

Define the terms ecliptic and the tropics. 

Define the term azimuth. 

What is meant by the term amplitude when applied to naviga¬ 
tion and astronomy ? 

What is the meaning of the term dead reckoning? 

Give the sailing distance from New York, in geographical miles, 
to different ports. 

Give the latitude and longitude of different seaports. 

To what class of machines do pumps belong? 

What principle is involved in the working of all pumps? 

How high will an ordinary pump, in good condition, lift water 
or other liquids ? 

What condition limits the action of all atmospheric pumps? 

Give the rule for finding the size of pump-plunger and stroke 
for an engine of any given power. 

Give the rule for finding the quantity of water, or other liquid, 
that any pump will lift or discharge in a given time. 

Give the most probable causes why pumps fail to work satis¬ 
factorily. 


THE ENGINEER’S HANDY-BOOIv. 441 

Explain the difference between lift force, single-acting, and 
double-acting pumps. 

What is the meaning of the term circulating-pump? 

What is the object of placing an air-chamber on a pump ? 

Give the rule for finding the power required to raise a given 
quantity of water. 

Give the reason why pumps will not lift very hot water. 

What is the object of placing a pet-cock on the barrel of a 
feed-pump ? 

What is the object of placing mud-boxes or strainers on the 
suction-pipes of pumps ? 

What course would you adopt to prevent pump-pipes from 
freezing in cold weather ? 

Explain the meaning of the terms injector and ejector when 
applied to hydraulic machines. 

Explain the principles involved in the working of the injector. 

What conditions limit the height to which injectors can lift water? 

Under what three heads may all injectors be classed? 

What are the meanings of the terms maximum and minimum 
delivery ? 

What is the meaning of the term range when applied to injectors? 

To what class of machines does the inspirator belong? 

On what principle is the action of the inspirator based? 

Explain the advantages and disadvantages of injectors, ejectors, 
and inspirators over pumps. 


PART SIXTH 


Steam-Boilers. 

Steam-boilers embrace a great variety of designs;* in fact, 
any vessel in which steam is generated for mechanical purposes 



may be termed a steam-boiler, regardless of shape or form. The 

* For a full description of all the steam-boilers in use at the present day, 
their peculiarities of design, construction, care, and management, see Roper’s 
“Use and Abuse of the Steam-Boiler.” 









































































































































































































































































































ihe engineer's handy- book. 443 

most co mm °„ forms of marine-boilers in use at the present day 
• e he horizontal and vert.cal, fire-and water-tubulars. The wate,- 

n^hS h ? P r n " g ’ a " d jS n0W rareI ^ t0 be f «und except 
United States Navy, or those of other countries. Its gradual 

^appearance anses fr ° m tbe that it is more expensive to build 

and to repair, is more dangerous, and requires extra care and man- 

,f a tl,be L S P llts or becomes leaky in the fire-tubular boiler, 
the difficulty may be met by plugging, and the vessel can proceed 
on its way; but if the same accident occur in a water-tubular, it 

1 "I • -| • | _ same principle which 

was embodied in the Montgomery water-tubular marine-boiler was 



Fire-Tubular Marine-Boiler. 

introduced into the Dimpfel locomotive-boiler, but soon fell into 
disuse m both cases. The fire-box, fire-tubular marine-boiler, with 




































































































444 


THE ENGINEER’S HANDY-BOOIv. 


combustion-chamber at the back end and superheater in the up¬ 
take, is the type of boiler most generally in use on the steamships 
of the different lines sailing out from the seaports of this country 
as well as those of other nations. 

Aside from the choice among engineers between the two forms, 
there is a wider difference in their proportion than in anything 
else connected with the steam-engine. While all generally agree 
that, in proportioning a marine-boiler, there should be sufficient 
grate-surface to consume the maximum quantity of coal required 
for the engine for which that boiler was intended to furnish steam, 
and that there should be sufficient heating-surface to absorb the 
heat evolved by the fuel; yet, when it comes to laying down pro¬ 
portions, one engineer allows twice as many square feet of heat¬ 
ing-surface to one square foot of grate-surface as another. Watt’s 
proportions for land- and marine-boilers varied from 9*5 to 10 feet 
of heating-surface to 1 square foot of grate-surface. Maudsley 
and Miller allowed 10 square feet of heating-surface to 1 square 
foot of grate-surface in the boilers of the celebrated ocean steamer 
Great Western, and from 10 to 12 square feet of heating-surface 
to 1 square foot of grate-surface in other marine-boilers that they 
constructed about the same time; so that neither they nor Watt 
seemed to have any fixed rule, nor did there appear to be any 
among naval constructors either in this country or England. 

This may be seen from the fact that the U. S. gun-boat Massa¬ 
chusetts had 34 feet of heating-surface to 1 square foot of grate- 
surface, while the Vixen, with the same-sized engine, had only 16 to 1. 
The merchant-steamer Constitution had 66 square feet of heating- 
surface to one square foot of grate-surface, while the Franklin, a 
steamship of nearly the same capacity, with engines of the same 
power, had only 28 to 1. The boilers of the celebrated steamships 
of the Collins Line, which have made such fast time between 
New York and Liverpool, had 33 square feet of heating-surface 
to 1 square foot of grate-surface, while in the boilers of the steam¬ 
ships of the Cunard Line the heating-surface varies from 18 to 37 
square feet to 1 square foot of grate-surface. The Mary Powell, 


THE ENGINEER’S HANDY-BOOK. 


445 


one of the fastest river-boats in American waters, has 17 square 
feet of heating-surface to 1 square foot of grate-surface. In pro¬ 
portioning the heating-surface to the cubic contents of the cylinder, 
the same variation seems to exist which shows there is no recognized 
proportion for either. The steamship Massachusetts, U. S. N., has 
77 square feet of heating-surface to 1 cubic foot of cylinder, while 
the Powhatan has less than 15 square feet, and the San Jacinto has 
a trifle over 12. The merchant-steamer Union had one hundred 
and eighteen square feet of heating-surface to 1 cubic foot of 
cylinder, while the Isaac Newton had only 10 to 1. The steam-tug 
Rescue had 63 square feet of heating-surface to 1 cubic foot of 
cylinder, while the Anglo-Saxon had only 10 to 1. 

The average proportion of heating-surface to grate-surface of 
345 steamships, tugs, and ferry-boats examined was about 30 
square feet of heating-surface to 1 square foot of grate-surface, 
while an examination of a great number of steamships, tug, and 
ferry-boats in this country, England, and France, showed that the 
average proportion of heating-surface to 1 cubic foot of cylinder 
was about 28. In stationary boilers the heating-surface varies 
from 12 to 30 to 1 square foot of grate-surface, while in some 
patented sectional boilers there are 60 to 70 square feet of heat¬ 
ing-surface to one square foot of grate-surface, the average for 
locomotive-boilers being about 60 square feet of heating-surface 
to 1 square foot of grate-surface. 

To proportion a marine-boiler understanding^, it is necessary 
to know the size of the engine and of the boat or ship, the load 
to be propelled, and the speed at which it is to move. The engi¬ 
neer can determine the pressure and volume of steam required, 
and decide on the degree of expansion, the quantity of grate- and 
heating-surface, and in relation to these two latter conditions, as 
shown in the foregoing paragraphs, the field has a very wide lati¬ 
tude. But he must be sure that the boiler possesses sufficient 
strength to resist in safety the maximum pressure to which it will 
ever be exposed; that it contains sufficient grate-surface for the 
combustion of the necessary quantity of fuel under any circum- 
38 


446 


THE ENGINEER’S HANDY-BOOK. 



stances; that it lias sufficient heating-surface to evaporate the nec¬ 
essary quantity of water; that it is capable of containing a suffi¬ 
cient supply of water and steam to prevent undue fluctuation, 
and that it affords convenient facilities for the repair or renewal 
of any of its parts. After the foregoing conditions are determined 
on, another object of great importance to be considered is making 
the boiler as light and compact as possible. The term heating- 
surface, when applied to steam-boilers, means all that part of the 
fire-box, crown-sheet, tube-sheets, and flues with which the fire and 
flame come in contact in their escape from the furnace to the 

chimney. 

Martin’s upright 
tubular - boiler is 
sometimes used for 
marine purposes. 
Its only advantage 
is economy of space; 
its first cost is more 
than that of the 
ordinary horizon¬ 
tal marine tubular- 
boiler, and it is not 
more efficient. The 
capacity of the 
steam-room is about 
one-third the capac¬ 
ity of the boiler. 

The quantity of 
steam that can be 
generated in any 
boiler in a given 
time is dependent 

upon a great varie- 
Direct Flue and Return Tubular Marine-Boiler. „ . 

ty ot circumstances, 

such as the kind of boiler, its condition as to dirt, scale, etc., the 



























447 


THE ENGINEER^ HANDY-BOOK. 

manner in which it is set and fired, the quality of the fuel used, 
quantity of grate-surface, amount of heating-surface, draught, 
etc., while the amount of water used will depend entirely on the 
engine, provided the steam is dry. The evaporation in tubular 
boilers,— stationary, locomotive, and-marine,— under good con¬ 
ditions, is about 8^ to 9 lbs. of water to 1 lb. of coal; in flue- 
boilers, 6 to 7; but the average result is about 25 per cent, below 
this. The nominal loss of fuel in boilers is rarely less than 30 
per cent., and is frequently as high as 50. Taking the lowest 
estimate at 30 per cent., it may be illustrated as follows: The 
amount necessary to produce a draught, including the flame which 
escapes into the chimney, 20 per cent.; particles of coal falling 
through the grates, 5 per cent.; loss arising from the formation of 
carbonic oxide, 3 per cent.; loss induced by radiation, 2 per cent. 

The common estimate of the quantity of water necessary to 
produce one horse-power is one cubic foot; the amount of heating- 
surface necessary to evaporate one cubic foot of water in an hour 
has been found, by experiment, to be about 14 square feet to £ 
square foot of grate-surface, under the most favorable conditions. 
It has grown into a custom, in estimating the horse-power of steam- 
boilers, to allow 14 square feet of heating-surface to ? square foot 
of grate-surface; but the evaporative performance of steam-boilers 
varies very much, as in one boiler a cubic foot of water may be 
evaporated in an hour by 9 square feet of heating-surface to i 
square foot of grate-surface, while another will take double the 
amount. In locomotives, the proportion of heating-surface to 
grate-surface is about 50 to 1; in marine-boilers, about 28 to 1; 
ordinary cylinder-boilers, about 15 to 1; flue-boilers, 18 to 1; 
tubular-boilers, from 20 to 24 to 1; and in sectional- or patent- 
boilers, about 30 to 1. 

The tendency of water to foam in marine-boilers is frequently 
attributed to the presence of dirt, or other saline matter, in the 
water; but it is often induced by want of proper relations between 
the heating-surface, steam-room, and water-space of the boiler, as, 
when the discharge of steam is out of proportion to the steam-room 


448 


THE ENGINEER’S HANDY-BOOK. 


in the boiler, the high temperature required to generate steam with 
sufficient rapidity to supply the demand causes violent boiling, and 
the agitation is greater when the relation between the temperature 
and pressure is most disturbed. This is often the case with 
tug-boats just starting to tow a heavy vessel. Boilers with a 
large amount of heating-surface and small steam-room generally 
foam. 

Marine-boilers are generally surmounted by a dome, and, 
though domes do not add much to the cubical capacity of the 
steam-room, they have the effect of superheating the steam, or 
imparting to it an «xtra heat, which greatly increases its expan¬ 
sive force, and renders it less liable to condense in the passages 
between the boiler and the cylinder. 

Fittings of marine-boilers. — The fittings of marine-boilers are 
the funnels, air-casings, uptakes, smoke-box and fire-doors, grate- 
bars, bearers and bridges, main steam-pipe and stop-valve, donkey- 
valve, safety-valves and drain-pipes, main- and donkey-feed check- 
valves, blow-off- and scum-cocks, water-gauges, test water-cock, 
steam-valves for whistle, and winches. 

Bursting Pressure of Cylindrical Steam-Boilers. 

The force which will rupture a cylindrical boiler depends upon 
the diameter and the pressure of the steam ; hence, the total press¬ 
ure to be sustained is equal to the diameter, multiplied by the 
pressure per square inch of surface, multiplied by the length of 
the boiler. The shorter the tube, and the smaller the diameter, 
the greater its power of resistance, and vice versa. No matter 
what the diameter of a boiler may be, the transverse, or cross 
pressure tending to tear it asunder, will always be double the 
longitudinal pressure. 

Rule for finding the bursting pressure of cylindrical boilers with 
riveted seams. 

Multiply the tensile strength of the iron (which should be taken 
at 50,000 lbs. per square inch of section) by *56, if single riveted, 
38 * 


THE ENGINEER’S HANDY-ROOK. 


449 


and by *70, if double riveted, and divide by the diameter of the 
boiler, multiplied by the number of pieces of metal, that would 
make one square inch of cross section ; the product will be the 
bursting strain. 

For instance, what pressure will it require to rupture a cyl¬ 
indrical boiler with riveted seams, diameter 12 inches, thickness 
of iron 1 inch ? 

50 000 x *56 

— X ~ ^3 ^3 X 2 = 1166*66 lbs., about one-fifth of 


which would be the safe working-pressure. 

Rule for finding the strain exerted in a longitudinal direction by 
the pressure of steam in a boiler. 

Multiply the area of the head by the pressure in pounds per 
square inch, and divide the product by the circumference of the 
boiler, and by the number of thicknesses of iron that would 
make one square inch of cross section ; the quotient will be the 
strain. 

a 

Example. Diameter, 12 inches. Area, 113*09 square inches. 
Pressure, 1166§ lbs. 


113*09 x 1166*66 
37*69 -=-4 


14014 lbs. per square inch of sectional area 


in a longitudinal direction. 

Rule for finding the strain exerted in a transverse direction by 
the pressure of steam in a boiler. 

Multiply the pressure per square inch by the diameter, and also 
by the number of thicknesses of metal it will take to make one 
square inch of cross section, and divide the product by 2, because 
the boiler has 2 sides. 

, 1166*66 x 12 x 4 oinnnQ1H . x 

Example. ---— 31999*84 lbs. per square inch 

A 


of sectional area in a transverse direction. 

The power of any steam-boiler to resist strain depends upon 
the thickness and quality of material, character of the workman¬ 
ship, and the shape of the parts subjected to strain. 

38* 2D 





450 the engineer’s handy-book. 



««• ••••••••••••• 


E o* o • • • • e • • » « 9 • • • *, 

a : ••©••••«.•••••••• 

**••»»• «9(tO • t O 


•909•«•«•••••••• 

• • • O « ••••••• ••••**«• 

• »«•••• 99 9»V*V. * 
® <!-V a e • o .a *•••©• 

f,V*V*»****'v°**! # Xv' 

1 »%»••• •©•»•••• © « 
«a«09 • 9 6 9(9 • • • • • 


53 

a 



The above cut represents the arrangements most generally em¬ 
ployed for bracing marine steam-boilers, and includes the vertical 
and horizontal, angle, toggle, dome, and crown braces; as well as 
the buckles, crow-feet, angle-irons, girths, stay-bolts, and leg braces. 
The tubes answer for braces for the tube-sheets; the crow-feet for 
the crown and dome; the proper strength for the braces of marine- 
boilers may be found by multiplying the number of square inches 
exposed to the pressure of the steam by six times the steam-press¬ 
ure to be carried. 




















































































































































THE ENGINEER'S HANDY-BOOK. 


451 


Rules. 

Rule for finding the safe working-pressure of iron boilers. — Multi' 
ply the thickness of iron by '56,* if single riveted, and *70, if 
double riveted; multiply this product by 10,000 (safe load): then 
divide this last product by the external radius (less thickness of 
iion), the quotient will be the safe working-pressure in pounds 
per squaie inch, which, it multiplied by 5, would give the burst¬ 
ing pressure. 

In the foregoing rule,. the tensile strength of the iron is taken 
at 50,000, as it has been repeatedly proved by experiment that 
boiler-plate possesses less tenacity than the same iron would have 
if rolled into bars. 

Rule for finding the internal strain to which boilers are subjected 
when under pressure. — Multiply the surface of the plate required 
for one square inch of sectional area by the pressure of steam in 
lbs. per square inch ; multiply this result by the diameter of the 
boiler in inches, and divide by 2, which gives the strain per square 
inch of sectional area to which the boiler is subjected. 

The surface of boiler-plate required for one square inch of 
sectional area will depend upon the thickness of plate; thus, iron 
\ inch thick will require 4 superficial inches to make one square 
inch of sectional area; iron l inch thick will require 2, and so on. 

Rule for finding the pressure per square inch of sectional area on 
the crown-sheets of steam-boilers. — Multiply the width of the'crown- 
sheet in inches by its Length in inches; multiply this product by 
the pressure of the steam in lbs. per square inch by the gauge; 
divide by 2, if I inch iron, and so on according to the thickness. 

Rule for finding the aggregate strain caused by the pressure of 
steam on the shells of boilers. — Multiply the circumference in inches 
by the length in inches; multiply that product by the pressure in 
pounds per square inch. The result will be the aggregate pressure 
on the shell of the boiler. 

* Multiplied by '56, because the iron loses 44 per cent, of its strength in the 
process of punching. Double-riveted seams equal '70 of the original strength. 



452 


THE ENGINEER’S HANDY-BOOK. 


Rule for finding the safe external pressure on boiler-flues. — Multi¬ 
ply the square of the thickness of the iron by the constant whole 
number 806,300; divide this product by the diameter of the flues in 
inches; divide the quotient by the length of the flue in’feet; divide 
this quotient by 3: the result will be the safe working-pressure. 

Rule for finding the collapsing pressure of boiler-flues. — Multiply 
the square of the thickness of the iron, in thirty seconds of an 
inch, by the constant number 262*4; divide this product by the 
length of the flue in feet; divide this quotient by the diameter of 
the flue in quarter feet, and the quotient will be the collapsing 
pressure in pounds per square inch. 

Rule for finding the number of square feet of heating-surface in a 
tube, or any number of tubes. 

Multiply the circumference of the tube in inches by its length 
in inches, and divide by 144 ; the quotient will be the number of 
square feet of heating-surface. This, multiplied by the whole num¬ 
ber of tubes, will give the aggregate amount of heating-surface. 

Rule for finding the strength of single- or double-riveted seams. 

Multiply the area of the metal between the holes, in square 
inches, by the ultimate strength of the metal after punching the 
holes. The product will be the strength of the seam. Single-riv¬ 
eted seams being equal to about 56 per cent, of the original 
strength, and double riveted, 70 per cent. 

Rule for finding the strain due to the pressure of the steam on 
boiler-stays. 

Multiply the area in inches between the stays by the pressure 
in pounds per square inch. The product will be the strain in 
pounds per square inch. 

Rules. 

Rule for finding the heating-surface of fire-box boilers — locomotive , 
marine, or stationary. — Multiply the length of the furnace-plates 
in inches by their height above the grate in inches; multiply the 
width of the ends in inches by their height in inches; multiply 
the length of the crown-sheet in inches by its width in inches; 


453 


THE ENGINEER’S HANDY-BOOK. 

also the combined circumference of all the tubes in inches by their 
length in inches; from the sum of these four products subtract the 
combined area of all the tubes and the fire-door; divide the re¬ 
mainder by 144, and the quotient will be the number of square 
feet of heating-surface. 

Rule for flue-boilers. — Multiply § of the circumference of the 
shell in inches by its length in inches; multiply the combined 
circumference of all the flues in inches by their length in inches ; 
divide the sum of these two products by 144, and the quotient 
will be the number of square feet of heating-surface. 

Rule for cylinder-boilers. —Multiply | of the circumference 
of the shell in inches by its length in inches, divide by 144, and 
the quotient will be the number of square feet of heating-surface. 

Rule for tubular-boilers. — Multiply f of the circumference of 
the shell in inches by its length in inches; multiply the combined 
circumference of all the tubes in inches by their length in inches. 
To the sum of these two products add f the area of both tube- 
sheets; from this sum subtract the combined area of all the tubes; 
divide the remainder by 144, and the quotient will be the number 
of square feet of heating-surface. 

Rule for finding the heating-surface of vertical tubular boilers , such 
as are generally used for fire-engines. — Multiply the circumference 
of the fire-box in inches by its height above the grate in inches. 
Multiply the combined circumference of all the tubes in inches 
by their length in inches, and to these two products add the area 
of the lower tube- or crown-sheet, and from this sum subtract the 
area of all the tubes, and divide by 144. The quotient will be 
the number of square feet of heating-surface in the boiler. 

Boiler-Stays. 

Boiler-stays, in any case, are but substitutes for real strength 
in the shell or other parts of the boiler. The strain usually al¬ 
lowed on them per square inch is about 5000 lbs. The most 
common method of securing them is to cut a thread on both ends, 


454 


THE ENGINEER’S HANDY-BOOK. 


and screw and cold-rivet them into the plates; another method 
is to flatten the ends of the stay, and secure them to the boiler 
by means of one or two rivets; still another is to rivet eye-bolts 
into the shell of the boiler, fork the end of the stay-bolt, and 
attach to the eye-bolt by means of a cotter. But all the forego¬ 
ing methods have their objections, as, when the stays become 
slack, and it becomes necessary to make them taut, the necessity 
of cutting away the rivets, destroying the thread, and weakening 
the boiler is necessarily involved. 

The most modern and permanent method of securing stays to 
the shell or ends of steam-boilers is by riveting angle-irons to 
the parts to be braced, as shown at a, a, a, a, in the cut on page 
450, and drilling holes in the angle-irons where the brace is to be 
attached. Then the rods may be forked, and attached to the 
angle-irons by means of a cotter, which term means a blank bolt, 
with a splint in its end, which may be expanded with a cold-chisel, 
to prevent them from coming out. This arrangement has this 
advantage, that, where the braces become slack, they may be 
made taut by taking them out, heating them in a forge, and up¬ 
setting them. The value of stays as a substitute for strength and 
safety depends very materially not only on the manner in which 
they are attached to the parts they are intended to strengthen, 
but also on their position, which affects their ability to stand ten¬ 
sile strain and compression-pressure. If the stay is properly 
anchored, it will stand, on a straight pull, a resistance equal to its 
tensile strength, or it will resist the force of compression equal to 
its crushing strength; but if it stands slightly oblique, its power 
of resistance will be very much diminished. 

Stay-Bolts. 

Stay-bolts are the means usually employed to strengthen the 
flat surfaces in the fire-box and water-legs of locomotives and 
marine-boilers; they are generally screwed into both plates, on 
each side of the water space, and riveted by the process called 


THE ENGINEER’S HANDY-BOOK. 


455 


cold riveting. Numerous ordinary-sized bolts are preferable to a 
few large ones. The difficulty in the case of stay-bolts does not 
arise ordinarily from tensile strength, brought upon the bolt by 
the steam-pressure, but from relative changes in position of the 
two sheets through which the bolt passes, caused by a difference 
in the temperature of the two sheets, and the consequent difference 
in expansion. For instance, if the side sheet of a fire-box of a 
locomotive- or marine-boiler expands in a vertical direction £ of 
an inch more than the outside sheet, then all bolts in the top row 
will have their inner ends forced upwards from their original 
position to that extent, and the boilers must spring or bend ac¬ 
cordingly ; whereas, when both sheets become again of the same 
temperature, the ends of the bolts are drawn back to their original 
position. * ' 

TABLE 


SHOWING THE BREAKING STRAIN OF IRON AND COPPER STAY-BOLTS. 



Breaking 
Weight in 
Pounds. 

Strength 
distributed 
over 25 
inches area 
would give 
Lbs. per 
square inch. 

Strengtli 
distributed 
over 1(> 
inches area 
would give 
Lbs. per 
square inch. 

1. Iron into iron screwed and ) 

riveted.) 

2. Iron into copper screwed } 

and riveted.j 

3. Iron into copper screwed | 

only ....... ( 

4. Copper into copper screw-) 

ed and riveted . ... \ 

25,000 

21.400 

16,200 

14.400 

1,000 

856 

648 

576 

1,563 

1,338 

■ • > • 

1,013 

900 


Scale in Steam-Boilers. 

Marine-boilers using sea-water require to be frequently blown 
out to prevent incrustation, or deposit of salt, on their heating 


























456 


THE ENGINEER’S HANDY- BOOK. 


surfaces, which lie between the iron and the water. It not only 
causes an increased consumption of coal, but allows the iron to 
become crystallized and burned. The evil effects of the scale are 
due to the fact that it is a non-conductor of heat. Its conducting- 
power, compared with that of iron, is as 1 to 35’5. Consequently, 
more fuel is required to heat water in an incrusted boiler than in 
the same boiler if clean. A scale y g inch thick will require the 
extra expenditure of 15 per cent, more fuel; this ratio increases 
as the scale thickens. Thus, when it is I inch thick, 60 per cent, 
more fuel is needed ; 1 inch thick, 150 per cent., and so on ; con¬ 
sequently, to raise water in a boiler to any given heat, the fire-sur¬ 
face of the boiler must be heated to a temperature in accordance 
with the thickness of the scale. 

To raise steam to a pressure of ninety pounds, the water must 
be heated to about 320° Fab. In a clean boiler of \ inch iron, 
this may be done by heating the external surface of the shell to 
about 325°. If ^ inch of scale intervenes between the shell and 
the water, such is its non-conducting power, that it will be neces¬ 
sary to heat the fire-surface to about 700°, almost red heat. Now, 
the higher the temperature at which iron is kept, the more rapidly 
it oxidizes, and at any heat above 600° it very soon becomes gran¬ 
ular and brittle, and is liable to bulge, crack, or otherwise give 
way to the internal pressure. This condition predisposes the boiler 
to explosions, and makes necessary expensive repairs. Again, it is 
readily seen that the presence of scale renders slower and more 
difficult the raising, maintaining, and lowering of steam. 

The principal ingredient in the scale which forms in marine- 
boilers using sea-water is sulphate of lime, but no very injurious 
effect will take place in boilers if the degree of saltness is not 
allowed to exceed In fact, a thin coat of scale is beneficial, as 
it protects the iron from corrosion and internal grooving. 

Lord’s Boiler Compound appears to be the only chemical prep¬ 
aration in use at the present day that will prevent the formation 
of scale, or remove it after it has been formed, in any class of 
boilers, whether stationary, locomotive, or marine, as it neutral- 


THE ENGINEER’S HANDY-BOOK. 457 

izes the action of the natural chemical salts which form the 
basis of all scale and incrustation. 

An analysis of sea-water shows the relative quantities of the 
ingredients it contains. 


Water .... 

. 964 745 

Chloride of Sodium . 

. 27-059 

Chloride of Potassium 

. 0-766 

Chloride of Magnesium . 

. 3-666 

Bromide of Magnesium . 

. 0-029 

Sulphate of Magnesia 

. 2-296 

Sulphate of Lime . 

. 1-406 

Carbonate of Lime . • . 

. 0-033 


The minerals which constitute the basis of the scale which 
forms in steam-boilers using fresh-water from wells, lakes, or 
rivers, are sulphate of lime, phosphate of lime, carbonate of lime, 
magnesia, silica, and alumina, with small quantities of sesquioxide 
of iron, baryta, carbonic acid, organic matter, chlorine, sulphuric 
acid, potassa, calcium, soda, phosphoric acid, magnesium, etc. 
The remedies for the prevention and removal of scale from steam- 
boilers are almost innumerable. 

Foaming in Marine-Boilers. 

Foaming in marine-boilers using jet-condensers is generally 
caused by changing the water from salt to fresh, or vice versa , and 
is made evident by the boiling up of the water in the glass gauge. 
When foaming arises from this cause, the water in the boiler should 
be changed as soon as possible, which can be done by putting on a 
strong feed, and blowing out continuously, or at short intervals; 
it may even become necessary to throttle down the engine, cut oft’ 
short, or even stop, in order to ascertain the level of the water in 
the boilers. 

Violent foaming can be checked by opening the furnace-door, 
closing the damper, and covering the fire with fresh coal; but this 
39 







458 the engineer’s handy-book. 

means of relief should be used as little as possible, because it has a 
tendency to injure the boiler, owing to the sudden contraction of the 
parts most exposed to the fire. A.11 the phenomena connected with 
foaming have not yet been satisfactorily explained, but, fiom 
whatever cause it may arise, it is always attended with a certain 
amount of danger. Foaming is sometimes confounded with prim- 
ing, but they arise from different causes, and are productive of dif¬ 
ferent results. Foaming is always made manifest by the violent 
agitation, the rising and falling of the water in the gauge, and 
the muddy appearance of the water. 

Foaming is induced in stationary boilers by a filthy condition, 
particularly in those to which the %d-water is supplied through 
open heaters, in consequence of the oil or tallow employed for 
lubricating the cylinder being carried over with the exhaust- 
steam. The water in locomotive-boilers foams on some parts of 
the road, while on other sections this phenomenon never mani¬ 
fests itself, which may be attributed to the presence of alkali or 
saline matter in the water with which the boilers are supplied on 
certain parts of the road. Foaming is induced in all boilers by 
the want of proper proportion between the water-space, heating- 
surface, and steam-room of the boiler, and also from the absence 
of sufficient steam-room in the boiler to supply the cylinder. 

Priming. 

The term Priming is understood by engineers to mean the 
passage of water from the boiler to the steam-cylinder in the 
shape of spray instead of vapor. It may go on unseen, but it is 
generally made manifest by the white appearance of the steam 
as it issues from the exhaust-pipe; as saturated steam, or steam 
containing water, has a white appearance, and descends in the 
shape of mist; while dry steam has a bluish color, and floats away 
in the atmosphere. Priming also makes itself known by a click¬ 
ing in the cylinder, which is caused by the piston striking the 
water against the cylinder-head at each end of the stroke. 

Priming is generally induced by a want of sufficient steam-room 


THE ENGINEER’S HANDY-BOOK. 


459 


in the boiler, the water being carried too high, or the steam-pipe* 
being too small for the cylinder, which would cause the steam in 
the boiler to rush out so rapidly that, every time the valve 
opened, it would induce a disturbance, and cause the water to rush 
over into the cylinder with the steam. 

The following table shows the result of a series of experiments-, 
carried out by Captain Rodman, for the purpose of demonstrating 
the effects of sudden strains on wrought-iron, a bar one inch 
square, of the best quality of iron, being selected for the purpose. 


Amount of Strain. 

Temp’y <Stretch. 

To°o°(5- °f an inch. 

Permanent Stretch. 
tVoit °f an inch. 

5,000 lbs. 

20 

0 

10,000 “ . 

41 

1 

15,000 “ .. 

57 

1 

20,000 “ . 

76 

3 

25,000 “ . 

100 

7 

30,000 “ . 

537 

408 

35,000 “ . 

1833 

1661 

40,000 “ . . 

4000 


45,000 “ broke. - 




It will be seen from the above table that the first essay, by 
means of a strain of 5000 lbs., produced no permanent stretch in 
the bar; and that 10,000 lbs. and 15,000 lbs., respectively, only 
produced a permanent stretch of T W°o of an inch, or about of 
the temporary stretch. But in the next two strains of 20,000 and 
25,000 lbs., the iron begins to shows a great acceleration of the 
weakening process or increase of fatigue, as the permanent strain 
has sprung up to of the entire stretch. In the next two items 
this acceleration is astounding, the permanent stretch being J of 
the whole upon 30,000 lbs, and T 9 0 of the permanent stretch of 
35,000 lbs. The tensile strength of good boiler-iron increases with 
an increase of temperature up to about 500° Fall., consequently, 
a steam-boiler is safer and stronger under a moderately high steam- 
pressure than it would be under the same hydraulic pressure. 

















460 the engineer’s handy-book. 

' Deterioration of steam-boilers. —Deterioration of steam-boilers 
arises from the following causes: want of lamination in the sheets; 
overstretching of the fibre of the plate in the process of rolling; 
injuries done the plate in the process of punching; damage in¬ 
duced by the use of the drift-pin ; injury done the plates by a 
want of skill in the use of the hammer, or in the processes of 
hand-riveting and calking. Other causes are unequal expan¬ 
sion and contraction, resulting from a want of skill in setting; 
grooving in the vicinity of the seams; internal and external 
corrosion; blowing out the boiler when under a high pressure, 
and filling it again with cold water when hot; allowing the fire to 
burn too rapidly after starting, when the boiler is cold; ignorance 
of the use of the pick in the process of scaling and cleaning; in¬ 
capacity of the safety-valve; excessive firing; urging or taxing 
the boiler beyond its safe and easy working capacity; allowing 
the water to become low, thus causing undue expansion ; deposits 
of scale accumulating on the parts exposed to the direct action of 
the fire, thereby burning or crystallizing the sheets or shell; and 
wasting of the material by leakage, etc. 

Corrosion, and its Analogy to Combustion.* 

The term corrosion means wasting, pitting, or grooving of the 
material, and is generally referred to under two heads, namely, in¬ 
ternal and external. 

Internal corrosion presents itself in various forms, and is due to 
various causes, but principally to the minerals and acids con¬ 
tained in the feed-water with which steam-boilers are supplied. 

External corrosion is said to be due to the galvanic action of 
the mineral in the fuel and the gases in the atmosphere, and both 
are intimately associated with combustion, or stimulated by it; as 
the acids and minerals which are in solution in the water, and lib¬ 
erated by the heat, attack the boiler internally; whilst the sulphur 
which is liberated by the combustion of coal has a strong affinity 


* See Roper’s “ Use and Abuse of Steam-Boilers.” 





461 


THE ENGINEER’S HANDY-BOOK. 

for the iron of which boilers are constructed, and attack it ex¬ 
ternally. 

Manual and Mechanical Firing. 

The term firing is understood to be the art of applying fresh 
coal or other fuel to a furnace, which operation, in the case of large 
furnaces, incurs the severest kind of manual labor, and is attended 
with a great loss of fuel, in consequence of the great volume of 
cold air that enters the furnace every time the operation of replen¬ 
ishing or cleaning the fires is performed. Numerous attempts 
have been made to obviate this waste by the invention of ma¬ 
chinery that would fire or supply the fuel continuously, but so far 
no mechanical arrangements have proved a success ; nor is it at all 
likely that they ever will, as there are difficulties to be encountered 
which no human ingenuity in the design of machines can prob¬ 
ably ever overcome. It is impossible to design a machine that 
will distribute the coal uniformly over the surface of the fire, in¬ 
cluding the sharp corners, etc. Unless that can be done, me¬ 
chanical firing, however ingenious the arrangement may be, must 
ever prove a failure. 

Even if a machine were devised that would distribute the fuel 
evenly over the fire-surface, it would not be available for cleaning 
the fires, and, as a result, there would be nearly the same loss in¬ 
curred if the fires have to be cleaned by hand, as if they were fed 
by hand. This being the case, the question would naturally be 
asked, Why is it that thousands of dollars have been expended in 
attempts to fire mechanically? and the answer would be, that there 
are always parties to be found who are ready to devote time and 
invest money in every delusion which has ever been promulgated 
in connection with the steam-engine and boiler. If fuel could be 
consumed in round or oval furnaces, it would render more service 
than if burned in square furnaces, as there is always more or less 
dead material in the square corners through which the air escapes, 
thus lowering the temperature in the furnace, and rendering com¬ 
bustion less active and more wasteful. 


462 


THE ENGINEER’S HANDY-BOOK. 


Technical Terms applied to Firing. 

Start Fires. — This term is understood to mean starting fresh 
fires in furnaces with shavings, wood, coal, etc. 

Bank Fires. —This term is understood to mean covering the 
fires down with a thick body of coal at night, or when the engine 
has to be stopped for an indefinite period. 

Slice Fires. —This means to push back the fire to the bridge- 
wall, and then draw out the cinders, after which the fire is drawn 
forward, distributed over the grates, and fresh fuel supplied. The 
terms slice and clean fires have the same meaning. 

Draw Fires. —This term is understood to mean to draw the 
entire fire from the furnace for the purpose of allowing the furnace 
to cool for stoppage or repairs, as the case may be. 

Technical Terms Employed in Relation to Boilers. 

Curvilinear Seams. — The curvilinear seams of a boiler are 
those around the circumference. 

Grate-Surface. —The term grate-surface means the aggre¬ 
gate number of square feet. In practice, the allowance of 
grate-surface is about three-fourths of a square foot per horse¬ 
power. 

Longitudinal Seams. —The seams which are parallel to the 
length of a boiler are called the longitudinal seams. 

Safe-working pressure, or safe load. — The safe-working press¬ 
ure of steam-boilers is generally taken as \ of the bursting press¬ 
ure, whatever that may be. 

Steam-Room. —That part of a boiler occupied by the steam. 
In practice, it is about \ of the cubic contents of the boiler. 

Water-Space. —That part of a steam-boiler which is occupied 
by the water. It is generally about f of the cubic contents of the 
boiler. 

The aggregate space in all classes of steam-boilers may be em¬ 
braced under two heads, viz., steam-room and water-space. 


THE ENGINEER’S HANDY-BOOK. 


463 


Friction of Riveted Seams. 

Owing to the contraction of rivets in cooling, the plates are, in 
many instances, brought into such close contact that the friction 
between them is sufficient to withstand the working strain without 
any shearing action coming upon the rivets. This is more especially 
the case with machine riveting. The contraction of a wrought- 
iron bar in cooling is nearly equal to iot>ofi of its length for a 
decrease of temperature of fifteen degrees Fah., and the strain 
thus induced is about one ton for every square inch of sectional 
area in the bar. 

Thus, if a rivet one inch in section were closed at a temperature 
of 900 degrees, it would in cooliug decrease in length yo^oo of 
its length ; and if its elasticity and strength remained perfect, would 
produce a tension of 60 tons. The ultimate strength of rivet iron, 
however, being only 24 tons, the rivet would in cooling be per¬ 
manently elongated, and would continue, when cool, to exert a 
tension of 24 tons, providing its elasticity remained uninjured by 
the strain. Thus, if the rivets were not in contact with the plates, 
excepting at the head and tail, the plates would be held together 
by a pressure of 24 tons, and this friction would have to be over¬ 
come before the rivet came into action as a mere pin, from which 
will be seen that, by judicious riveting, the friction may, in many 
cases, be nearly sufficient to counterbalance the weakening of the 
plate from the punching of the holes. 

Calking. 

The object of calking is to bring together the seams of boilers, 
tanks, or hulls of iron vessels after riveting, so that they may be 
perfectly steam- or water-tight. This is done by using a sharp 
tool ground to a slight angle. The edge of the plates being first 
chipped or planed to an angle of about 110°, the calking-tool is 
applied to the lower edge of the chipped or planed angle, in order 
to drive or upset the edge, thus bringing the plates together, and 


464 


THE ENGINEER^ HANDY-BOOK. 


rendering the joint to all appearances perfectly steam-tight, and 
able to resist the internal pressure brought to bear upon this 
particular point. There are different methods of calking, but 
the concave method has many points of preference over any 
other. Boilers should never be calked while under steam- or water- 
pressure, however light, as the jarring induced by the calking is 
liable to spring the seams and cause fresh leakage in other parts 
of the boiler. 

Steam-Boiler Explosions. 

The principal causes of explosions,* in fact, the only causes, 
are deficiency of strength in the shell or other parts of the boilers, 
over-pressure and over-heating. Deficiency of strength in steam- 
boilers may be due to original defects, bad workmanship, deterio¬ 
ration from use or mismanagement. Deficiency of strength aris¬ 
ing from bad workmanship is the most difficult to discover, and 
not unfrequently escapes the closest scrutiny, more particularly in 
the case of flue, tubular, and locomotive boilers. 

Gver-pressure may be caused by the safety-valve being over¬ 
weighted ; by its sticking on its seat; by the inadequate size of 
the communication between the boiler and valve, or by an incorrect 
and worthless steam-gauge. The same effect may be produced 
when there is a disproportion between the grate- and heating- sur¬ 
faces, or where the heat from a large grate is concentrated on a 
small space. Under such circumstances, the heat is delivered with 
such intensity as to lift the water from the surface of the iron, 
thereby exposing it to the direct action of the fire. 

Explosions occurring from excessive firing are in all cases the 
result of avarice, ignorance, or a want of skill in the care and 
management of the steam-boiler. Overheating may be caused 
by the accumulation of hard, solid incrustation adhering to the 
parts most exposed to the direct action of the fire, or it may be 
due to insufficiency of water, resulting from leakage of the valve 


* See Roper’s “ Use and Abuse of the Steam-Boiler.” 



THE ENGINEER^ HANDY-BOOK. 


465 


or stop-cock, a failure in the supply-pipe, or a neglect to turn it 
on at the proper time or in sufficient quantity. 

A steam-boiler may be well designed, of good material, and of 
first-class workmanship, and yet in a few months, after being put 
under steam, it may explode with terrible effect. On examining 
into the cause of the explosion, it may turn out that the water 
used made a heavy deposit; that the boiler had not been cleaned 
since it was put into use; that the fires had been fiercely urged, 
and the water driven from the surface of the iron ; as a result, 
the life had been entirely burned out of the sheets over and around 
the fire, thereby weakening the boiler, and putting it in a dan¬ 
gerous condition. That the sudden heating or cooling, and oxida¬ 
tion of the boiler, induce great deterioration of strength has 
been proved by experience. Defects in the material, as blisters, 
lamination arising from inferior material, or want of care in the 
manufacture, are other sources of weakness in steam-boilers. 

Safety-Valves.* 

The safety-valve is designed on the assumption that it will rise 
from its seat under the statical pressure in the boiler, when this 
pressure exceeds the exterior pressure on the valve, and that it 
will remain off its seat sufficiently far to permit all the steam 
which the boiler can produce to escape around the edges of the 
valve. The problem then to be solved is: What amount of open¬ 
ing is necessary for the free escape of steam from a boiler under a 
given pressure? The area of a safety-valve is determined from 
formulae based on the velocity of the flow of steam under different 
pressures, or experiments made to ascertain the area necessary for 
the escape of all the steam a boiler could produce under a given 
])ressure. But as valves do not rise appreciably from their seats 
under varying pressures, the point to be considered is, how high 
any safety-valve will rise under the influence of a given pressure. 
This question cannot be determined theoretically, but has been 
settled conclusively by Burg, of Vienna, who ascertained from 


* See page 654. 







466 


THE ENGINEER’S HANDY-BOOK. 


careful experiments that the rise of the valve diminishes rapidly 
as the pressure increases, as may be seen from the annexed table. 


Pressure in Lbs. 

Pise of Valve. 

Pressure in Lbs. 

Rise of Valve. 

12 

l 

3 6" 

60 

■ffff 

20 

1 

48 

70 

i 

1 3 T 3 

35 

1 

S 4 

80 

T68 

45 

1 

90 

1 

168 

50 

ge 




In ordinary safety-valves, the average rise for pressures ranging 
from 10 to 40 pounds is about ^ of an inch; from 40 to 70 pounds, 
about -gtj, and from 70 to 90, about T ^-g- of an inch. The following 
table gives the result of a series of experiments made at the Nov¬ 
elty Iron Works, New York, some years ago, for the purpose of 
determining the exact area of opening necessary for safety-valves, 
per each square foot of heating-surface, at different boiler press¬ 
ures. 


Boiler Pressure 
in Lbs’. Above 
the Atmos¬ 
phere. 

Area of Orifice in 
Sq. In. for Each 
Sq. Ft. of Heat¬ 
ing-Surface. 

Boiler Pressure 
in Lbs. Above 
the Atmos¬ 
phere. 

. . 1 

Area of Orifice in 
Sq. In. for Each 
Sq. Ft. of Heat¬ 
ing-Surface. 

0-25 

*022794 

40- 

•001723 

05 

•021164 

50* 

•001389 

1- 

•018515 

60- 

•001176 

2* 

•014814 

70* 

•001015 

3* 

•012345 

80* 

•000892 

4* 

•010582 

90* 

•000796 

5* 

♦009259 

100- 

•000719 

10* 

•005698 

150- 

•000481 

20* 

•003221 

200- 

•000364 

30* 

•002244 




Now, if we compare the area of openings, according to these 
experiments, with Zeuner’s formula, which is entirely theoretical, 




































THE ENGINEER^ HANDY-BOOK 


467 


it will be observed that the results from the two sources are al¬ 
most identical. 

The lift of safety-valves, like all other puppet-valves, decreases 
as the pressure increases; but this seeming irregularity may be 
explained as follows: a cubic foot of water generated into steam 
at one pound pressure per square inch above the atmosphere will 
have a volume of about .1600 cubic feet. Steam at this pressure 
will flow into the atmosphere with a velocity of 482 feet per sec¬ 
ond. Now, suppose the steam was generated in five minutes, or in 
300 seconds, and the area of an orifice to permit its escape as fast 
as it is generated be required, 1600 divided by 482 X 300 will give 
the area of the orifice, If square inches. If the same quantity 
of water be generated into steam, at a pressure of 50 pounds 
above the atmosphere, it will possess a volume of 440 cubic feet, 
and will flow into the atmosphere with a velocity of 1791 feet per 
second. The area of an orifice, to allow this steam to escape in 
the same time as in the first case, may be found by dividing 440 
by 1791 X 300 ; the result will be square inches, or nearly ^ of 
a square inch, the area required. It is evident from this that a 
much less lift of the same valve will suffice to discharge the same 
weight of steam under a high pressure than under a low one, be¬ 
cause the steam, under a high pressure, not only possesses a re¬ 
duced volume, but a greatly increased velocity; it is also obvious 
that a safety-valve, to discharge steam as fast as the boiler can 
generate it, should be proportioned for the lowest pressure. 

There does not appear to be any recognized rule among boiler 
makers for proportioning safety-valves, since, while one allows one 
inch of area of safety-valve to every 66 square feet of heating- 
surface, another gives 1 inch area of safety-valve to every 4 horse¬ 
power, while a third allows 1 inch area of safety-valve to If square 
feet of grate-surface. This last proportion has been proved by 
experience to be capable of admitting of a free escape of steam, 
without allowing any greater increase of pressure than that for 
which the valve is loaded, providing that all the parts are in good 
working order. It is obvious, that no valve can act without a 


468 


THK ENGINEER’S HANDY-BOOK. 


slight increase of pressure, as, in order to lift at all, the internal 
pressure must exceed that of the load. Doubtless, most safety- 
valves are larger than is actually required, and but few boiler 
explosions occur from want of safety-valve area. The most prob¬ 
able causes of accidents arising from safety-valves are that they 
are either overloaded or out of order. A badly proportioned 
safety-valve, whether too large or too small, is objectionable, and 
is always attended with a certain amount of danger. 


Rules. 

Rule for finding the weight necessary to put on a safety-valve lever, 
when the area of valve, pressure, etc., are known. — Multiply the 
area of valve by the pressure in pounds per square inch ; multi¬ 
ply this product by the distance of the valve from the fulcrum ; 
multiply the weight of the lever by one-half its length (or its 
centre of gravity); then multiply the weight of valve and stem 
by their distance from the fulcrum: add these last two products 
together; subtract their sum from the first product, and divide 
the remainder by the length of the lever; the quotient will be the 
weight required. 

Rule for finding the pressure per square inch when the area of 
valve, weight of hall, etc., are known. — Multiply the weight of ball 
by the length of lever, and multiply the weight of lever by one- 
half its length (or its centre of gravity) ; then multiply the weight 
of valve and stem by the distance from fulcrum. Add these three 
products together. This sum divided by the product of the area 
of the valve, and its distance from the fulcrum, will give the press¬ 
ure in pounds per square inch. 

Rule for finding the pressure at which a safety-valve is weighted 
when the length of lever, weight of ball, etc., are known. — Multiply 
the length of the lever in inches by the weight of the ball in 
pounds; then multiply the area of valve by its distance from the 
fulcrum; divide the former product by the latter; the quotient 
will be the pressure in pounds per square inch. 


THE ENGINEER’S HANDY-BOOK. 


469 


Rule for finding centre of gravity of taper-levers for safety-valves, 
— Divide the length of lever by two (2); then divide the length 
of lever by six (6); and multiply the latter quotient by width of 
large end of lever, less the width of small end, divided by width 
of large end of lever plus the width of small end. Subtract this 
product from the first quotient, and the remainder will be the dis¬ 
tance in inches of the centre of gravity from large end of lever. 

Dead-weight safety-valves are those in which a pressure is 
exerted on the valve by means of a weight suspended on the long 
arm of the lever. 

Spring safety-valves are those in which the pressure of the 
steam against the face of the valve is resisted by means of a spiral 
spring. They are generally used for locomotives, as, in consequence 
of the jar, the dead-weight safety-valve is impracticable. 

Lock safety-valves are those in which the weight on the lever 
is enclosed in a lock-box, to prevent the engineer from increasing 
the pressure at will. This arrangement of safety-valve is most 
generally used on the boilers of marine engines, tug-boats, and 
ferries. 

Draught in Chimneys. 

The presence of draught in any locality is due, to a certain ex¬ 
tent, to the unbalanced pressure of the atmosphere, and is, in 
many cases, intensified and heightened by natural causes, but 
more frequently by mechanical and artificial arrangements. The 
natural draught or rush of air up chimneys or funnels is caused by 
the buoyancy both of the rarefied atmosphere and of the gases 
which pass through the fuel, as well as by the natural affinity of 
the colder and denser atmosphere to rush in and fill up the vacuum 
caused by the escape or ascension of the preceding volume. All 
the phenomena connected with draught are not as well understood 
as they should be, considering its importance as an agent in the 
promotion and maintenance of the combustion of fuel; the object 
of draught being to supply oxygen to the burning fuel, and dissemi¬ 
nate or eject the products of combustion. 

40 


470 


THE ENGINEER’S HANDY-BOOK. 


Numerous attempts have been made at different times to lay¬ 
down rules for the area and height of chimneys that would produce 
sufficient draught for the consumption of a certain quantity of 
fuel in a given time, but such formulae have more frequently failed, 
than succeeded, in giving satisfactory results, which is due prob¬ 
ably to the want of knowledge of the requirements in each in¬ 
dividual case, and of the location and surroundings. Attempts 
are, in many instances, made to produce a good draught by carry¬ 
ing the chimney above all surrounding objects and buildings, but it 
frequently occurs that shorter chimneys of the same area and 
internal dimensions have a better draught. It is claimed by some 
engineers that chimneys ought to increase in area from bottom to 
top, to be capable of producing a good draught, while others assert 
just the reverse, and claim that they ought to decrease from bottom 
to top. It has been found by experiment that both arrangements 
produced a good draught under some circumstances, but neither 
of them under all circumstances. The area of any chimney should 
increase slightly from bottom to top, in order to provide for the 
increased volume of the heated air and gases resulting from their 
expansion. It has been found that round flues produced a better 
draught, as a general thing, than either square or oval ones of the 
same area and height. This doubtless arises from the fact that 
air, rushing through or up a flue or funnel, has a tendency to as¬ 
sume the form of a screw, which is due probably to some natural 
cause. 

Adverse currents and capping winds frequently interfere with the 
draught in short chimneys, but the same effect is frequently pro¬ 
duced on tall ones during some kinds of weather and at certain 
seasons of the year; certain it is, that very tall stacks do not pro¬ 
duce a corresponding draught in proportion to the height, and it 
has been demonstrated by observation that there is nothing to be 
gained by raising chimneys very high. It often occurs that chim¬ 
neys of apparently sufficient height are incapable of producing 
sufficient draught. This, in many instances, arises from the fact 
that the quantity of fuel consumed in the furnace will not produce 


THE ENGINEER’S HANDY-BOOK. 


471 


sufficient beat in the flue to rarefy the air and cause draught, while 
in other chimneys of ample height and area, in consequence of 
the air and heated gases having to pass through a long, cold flue 
between the boiler and chimney, the draught is sluggish and unsatis¬ 
factory. There is no lack of formulae for proportioning chimneys, 
which have been furnished by Wye Williams, Rankine, Weisbach, 
Trowbridge, Steel, Watt, and others, but each is only applicable 
in certain cases; and indeed it appears that Watt knew as much 
about proportioning the flue as any of our modern engineers, 
which may be inferred from the fact that modern writers on the 
subject refer to him as frequently as to any one else. This goes 
to show that we have not made such rapid advances in mechanical 
science, so far as regards proportioning chimneys to produce good 
draught under all circumstances, as might have been expected, con¬ 
sidering the intelligence of the present generation and the pro¬ 
gressive ingenuity of the age. 

There are always individuals to be found who can tell how to 
proportion a chimney or a flue that will produce a draught sufficient 
to carry off the smoke and waste gases resulting from the con¬ 
sumption of a certain quantity of fuel, but they rarely ever ex¬ 
plain all the conditions under which this may be accomplished; 
such as the distance between the furnace and chimney; whether 
the flue is perfectly straight, or contains a number of bends; and 
whether in its course it ascends or descends. Such information 
is akin to that which tells engineers that a pound of coal will 
evaporate 8 or 9 lbs. of water, but never gives the conditions under 
which it may be done, which include the type or design of boiler, 
the quality of the iron, the condition of the boiler for cleanliness, 
etc., the purity of the fuel, and the intelligence and experience 
of the care and management. It is well known to most experienced 
engineers that the boiler that will evaporate 9 lbs. of water per 
lb. of coal under some circumstances, will not evaporate over 5 
lbs. of water per lb. of coal under others, and the results will be 
about the same in regard to draught. 

A forced draught may be produced by various mechanical ar- 



472 


THE ENGINEER^ HANDY-BOOK. 


rangements, such as blowing-engines, fan-blowers, steam-jets, etc.; 
but, although it may be suitable, and even an absolute necessity 
in the prosecution of many branches of mechanical industries, a 
forced draught is objectionable in assisting the combustion of fuel 
for the generation of steam in ordinary steam-boilers, and never 
fails to induce mischievous effects, and consequently a good natural 
draught is very much to be preferred when attainable. Any flue 
ought to be as smooth on the inside as circumstances will permit, 
in order to diminish the friction between the walls of the flue and 
the escaping air and gases. And in regard to the height of chim¬ 
neys and proportions of flues, it is always better to be governed 
by such practice as has given satisfaction in that locality, and 
with a particular kind of fuel, than to be guided by any theory, 
however scientific. The sectional area of the flue is what is termed 
the calorimeter of the boiler, and the calorimeter, divided by the 
length of the flue in feet, is termed the vent. The flues of all 
boilers diminish in their calorimeter as they approach the chim¬ 
ney, as the smoke contracts in volume in proportion as it passes 
through the heat. 

Funnels. —The area of the funnels of steamships, tug-boats, and 
ferry-boats varies considerably with different builders and in dif¬ 
ferent countries. The number of circular inches per nominal horse¬ 
power is given in the following table, for several makers. 


Highest, 15T4 
Mean, 14*10 
Low, 13*01 


Highest, 12*96 
Mean, 11*79 
Low, 10*89 


Highest, 14*45 
Mean, 13*94 
Low, 12*96 


Highest, 10*40 
Mean, 15*94 
Low, 15*14 


Highest, 1406 
Mean, 13*12 
Low, 12*17 


Mean Total, 13*78 


These are all for low pressures. For high pressure, the num¬ 
ber of inches varies from 9*11 to 6*02, mean 7'07. The funnel 
should evidently bear a proportion to the amount of heated air 
and smoke passing through it, which must bear a nearer propor¬ 
tion to the horse-power than to the surface of the fire-grate. 
Where the fire-grate is small, a large quantity must be burned per 
square foot. If, in one case, 20 lbs. of coal are burned per square 
foot per hour, and in another 40 lbs., and the funnels are propor- 






THE ENGINEER^ HANDY-BOOK. 473 

tioned to the fire-grate, they will not be proportioned to their re¬ 
quirements. 

Rule for finding the required area for the chimneys of stationary 
boilers .— Multiply the nominal horse-power of the boiler by 112, 
and divide the product by the square root of the height of the 
chimney in feet. The quotient will be the required area in square 
inches. 

A well-proportioned and moderately high smoke-stack is to be 
preferred for sea-going steam-vessels, as tall ones are difficult to 
steady on account of the oscillation of the vessel, arising from the 
disturbance of the water and the resistance of the wind. 

Superheaters. — Superheaters are steam-chambers located in 
the uptakes of marine-boilers or at the base of the funnel, and so 
arranged that the waste heat from the furnaces may pass around 
and through them, prior to escaping up the chimney. They are 
used for drying the steam in its transit from the boilers to the 
steam-cylinders of the engines. The heat or flame passes through 
the tubes and around the shell, the steam being inside. They are 
fitted with a stop-valve, and arrangements for mixing the super¬ 
heated and saturated steam, or using either independently; they 
also have safety-valves similar to those used on steam-boilers. 
There is no definite size for superheaters, as they are not intended 
for a receptacle for any large amount of steam, but simply as a 
means of drying it. The proportionate area of superheating to heat¬ 
ing surface in modern marine-boilers is about 1 to 10 square feet. 

An intercepter or separator is a chamber attached to marine- 
boilers for the purpose of intercepting the water carried out by the 
steam. The steam enters at the top and strikes against a partition 
plate, then passes under it and escapes to the cylinder; the water 
which enters with the steam is collected in the bottom of the box 
and drawn off* through a valve. 

Smoke. 

Smoke once formed in a furnace, flue, or chimney can never 
be burned by any mechanical device or arrangement, nor can there 
40* 


474 


THE ENGINEER’S IIANDY-ROOK. 

be any advantage in incurring much expense in the attempt, ex¬ 
cept to abate a nuisance, as very little economy in fuel would re¬ 
sult from the adoption of any such device. A very general idea 
prevails that, when we see large volumes of smoke issuing from 
the mouths of the chimneys of stationary boilers, smoke-stacks 
of locomotives, and funnels of marine-boilers, whenever fresh fuel 
has been applied, a great waste of fuel is taking place; this, how¬ 
ever, is a mistake, as about y 0 of the volume is steam resulting 
from the moisture expelled from the coal, wood, or shavings by 
the application of heat; besides, sulphur and other earthy matters 
which, like the steam, are incombustible, enter into and increase 
the volume. 

This may be easily explained by stating that 4 ton of water is 
converted into steam in the furnace for every ton of bituminous 
coal consumed, which is an actual benefit, because, if the carbon 
had not been thoroughly mixed with such a great mass of steam, 
it would have fallen in the shape of a black cloud of dust in the 
locality where the furnace was situated, and have become a more 
insufferable nuisance than the smoke. Smoke contains about 20 
per cent, of combustible and 80 per cent, of incombustible matter. 
Such being the case, the question would naturally arise, Would it 
be advisable to incur much expense in au attempt to consume 80 
per cent, of incombustible matter, for the purpose of gaining 20 
per cent. ? 

Feed-Water Heaters. 

The benefits to be derived from heating the feed-water for 

boilers by exhaust steam may be explained as follows: A pound 
of feed-water entering a steam-boiler at a temperature of 50° Fab., 
and evaporated into steam of 60 lbs. pressure per square inch, re¬ 
quires as much heat as would raise 1157 pounds of water 1 degree. 
A pound of feed-water raised from 50° Fall, to 220° Fall, requires 
987 thermal units of heat, which, if absorbed from exhaust steam 
passing through a heater, would be a saving of 15 per cent, in 
fuel. Feed-water, at a temperature of 200° Fall., entering a boiler, 


THE ENGINEER’S HANDY-BOOK. 


475 


as compared in point of economy with feed-water at 50°, would 
effect a saving of over 13 per cent, in fuel; and with a well con¬ 
structed heater there ought to be no trouble in raising the feed- 
water to a temperature of nearly 212° Fall. 

If we take the normal temperature of the feed-water at 60°, 
the temperature of the heated water at 212°, and the boiler-press¬ 
ure at 20 lbs., the total heat imparted to the steam in one case is 
1192*5° — 60° — 1132*5°, and in the other case 1192*5° — 212° = 

159 

980*5°, the difference being 152°, or a saving in fuel of 

1 loZ'D 

— 13*4 per cent. Supposing the feed-water to enter the boiler at 
a temperature of 32° Fah., each pound of water will require about 
1200 units of heat to convert it into steam, so that the boiler will 
evaporate between 61 and 71 pounds of water per pound of coal. 
The amount of heat required to convert a pound of water into 
steam varies with the pressure, as will be seen by the following 
table: 

TABLE 

SHOWING THE UNITS OF HEAT REQUIRED TO CONVERT ONE POUND OF 
WATER, AT THE TEMPERATURE OF 32°, INTO STEAM AT DIFFERENT 
PRESSURES. 


Pressure of 
Steam in Lbs. 

PER SQUARE 

inch by Gauge. 

Units of Heat. 

Pressure of 
Steam in Lbs. 

PER SQUARE 

inch by Gauge. 

Units of LIeat. 

1 

1*148 

110 

1T87 

10 

1*155 

120 

1*189 

20 

1T61 

130 

1*190 

30 

1*165 

140 

1*192 

40 

1*169 

150 

1T93 

50 

1*173 

160 

1T95 

60 

1T76 

170 

1*196 

70 

1*178 

180 

1*198 

80 

1*181 

190 

1T99 

90 

1*183 

200 

1*200 

100 

1*185 














476 


THE ENGINEER^ HANDY-BOOK. 


If the feed-water has any temperature, the heat necessary to 
convert it into steam can easily be computed. Suppose that its 
temperature is 65°, and that it is to be converted into steam hav¬ 
ing a pressure of 80 lbs. per square inch, the difference between 
65 and 32 is 33; subtracting this from 1181 (the number of units 
of heat required for feed-water having a temperature of 32°), the 
remainder, 1148, is the number of units for feed-water with the 
given temperature. 

Technical Terms applied to Adjuncts of the Steam-Boiler. 

Angle-irons. — Irons used for the purpose of staying steam- 
boilers. See page 400. 

Air-casing. — An arrangement attached to fire- and smoke-box 
doors for the purpose of preventing radiation of heat. 

Blast-pipe. — A small pipe used to blow steam into the fun¬ 
nels of marine-boilers for the purpose of exciting the draught in 
the furnace. 

Blow-off cocks. —Cocks used for blowing the water out of 
steam-boilers. 

Check-valve. — A valve used to retain the water in steam- 
boilers, and relieve the feed apparatus from the pressure. 

Check-chamber. —The chamber in which the check-valve 
operates. 

Connecting-pipes. — The pipes which connect check-valves with 
steam-boilers. 

Crown-sheet. —That part of fire-box boilers (locomotive or 
marine) directly over the fire. 

Crown-bars. —Bars placed on the upper side of crown-sheets, 
in the water-space, for the purpose of strengthening them. 


THE ENGINEER’S HANDY-BOOK. 


477 


Crown-braces. — Braces attached to the crown-bars, and to the 
shells and domes of boilers, for the purpose of resisting the press¬ 
ure exerted on the flat surfaces of crown-sheets. 

Dashers. — Iron plates which are sometimes attached to the in¬ 
side of steam-boilers to prevent the cold water, as it enters, from 
striking the tubes. 

Dead-plate. —The solid iron plate which fills the space between 
the end of the grate-bars and the fire-door of boiler-furnaces. 

Deflector. —An arrangement employed, in the furnaces of loco¬ 
motives and marine-boilers, for the purpose of mixing the air and 
gases arising from the combustion of the fuel, and causing them 
to ignite. 

Diaphragm-plate. —A perforated plate, used in the steam-domes 
of locomotives and marine-boilers, to prevent the water from being 
carried over into the cylinder with the steam. 

Dome. —An elevated chamber on the top of steam-boilers, from 
which the steam is generally taken for the cylinders. 

Dome-stays. — Stays employed, in the domes of locomotives and 
marine-boilers, for the purpose of strengthening them. 

Gasket. —A packing employed for making the man- and hand¬ 
holes of steam-boilers steam- and water-tight. 

Gauge-cocks. — Cocks used on the front-head of steam-boilers 
by which to ascertain the height of the water. 

Grummet. — A packing of hemp, used between the flanges of 
steam- and water-pipes, for the purpose of making them steam- 

and water-tight. 

* 

Stay-tubes. — Tubes used for bracing marine-boilers. They are 
generally made of thicker material than either the ordinary fire- 
or water-tubes. 



478 


THE ENGINEER’S HANDY-BOOK. 


Spanner-guard. — An arrangement employed to secure cocks 
and valves, connected with marine-engines and boilers, from being 
opened or closed by accident. 

Scum-cocks. —Cocks employed to blow off extraneous sub¬ 
stances from the surface of the water in steam-boilers. 

Spectacles. — Pieces of iron, with concave sides, employed as 
braces between the tubes of marine-boilers, generally for the pur¬ 
pose of stopping leaks. 

Tube-sheets. —The sheets into which the tubes are inserted at 
each end of the boiler. 

Knees. — Brackets riveted to the sides of steam-boilers, for the 
purpose of sustaining them on their supports. 

Waist. —A term applied to the cylindrical part of locomotive- 
or marine-boilers. 

Instructions for the Care and Management of Steam- 

Boilers. 

On first entering a boiler-room in the morning, ascertain whether 
the water stands at the proper level or not. 

Never start a fire under a boiler until you are satisfied there is 
sufficient water in it. 

On taking charge of an engine and boiler, first ascertain if 
there is sufficient water in the boiler, and then trace out the pipes 
and connections between the engine, boiler, and pumps. 

In starting a fresh fire under a boiler while it is cold, always 
allow it to burn gradually at first, in order to bring all the parts 
of the boiler to a uniform temperature. 

Never blow out a boiler under a head of steam, as the heat 
remaining in the boiler will bake the scale and mud on the sheets 
and flues, after which it will be impossible to soften it again. 


the engineer’s handy-book. 


479 


When preparing to clean boilers, allow them to cool down, 
and the water to remain in them until ready to commence clean¬ 
ing. 

Never fill a boiler with cold water while the shell, flues, or 
tubes are hot, as the contraction induced by the tube in cooling 
will have an injurious effect. 

Boilers, under which a forced draught is used, require to be 
cleaned oftener than when the draught is natural. 

Never carry a higher pressure of steam than is necessary, nor 
allow the water to rise above the second gauge-cock in the boiler 
when the engine is running. 

Before starting a fire under a boiler, place a small quantity of 
coal on the grates, to prevent them from being warped by the 
extra heat of the new fire. 

Boilers should be cleaned and examined inside and out every 
three months. 

Never neglect to blow out and clean boilers, even although 
solvents are used for the prevention and removal of scale. 

Never put a new boiler into service until examined thoroughly 
for the purpose of ascertaining if the boiler-makers have neglected 
to remove all lamps, hammers, tools, etc. 

Never open a steam-valve, on a boiler under pressure, quickly, 
for the purpose of allowing steam to escape into the atmosphere, 
or into a boiler containing a less pressure, as it is attended with a 
certain amount of danger, and may possibly produce an explo¬ 
sion. 

Clean the flues or tubes of the boiler at least once a week, and ' 
never allow ashes or cinders to accumulate under the grates. 

Never throw water around the furnaces of fire-box boilers. 

If the water should, from any unforeseen cause, become danger¬ 
ously low, draw the fire, allow the boiler to cool down, and neither 
admit feed-water nor disturb the safety-valve. 

In case the supply of water should be temporarily cut off, owing 
to the derangement of a pump, the bursting of a pipe, or any other 
cause, stop the engine, cover the fire with fresh coal, and shut the 



480 


THE ENGINEER’S HANDY-BOOK. 


damper, so as to retain a sufficient quantity of water in the boiler 
to start on. 

When it becomes necessary to blow out a certain quantity of 
the water from a boiler every day, the hand should never be re¬ 
moved from the cock or valve, as any diversion of a person’s at¬ 
tention from it may allow too much to be blown out, and the 
boiler be ruined. 

In all cases where it is possible, regulate the feed-water so as to 
send it into the boiler in a steady stream. 

When fresh water is used in marine-boilers, it is best to use salt 
water for a short time when first put into use, in order to cover 
the parts with a thin coat of scale. This prevents them from 
being injured by the action of fresh water. 

The term salting marine-boilers, means that the flues, tubes, 
and crown are covered with a thick coating of salt, which prevents 
the water from coming in contact with the iron. This induces 
cracking and burning of the parts so coated, besides causing a 
great waste of fuel. 

The parts of marine-boilers most likely to suffer from an in¬ 
sufficiency of water are the tubes and crowns ; but the water can¬ 
not become low in marine-boilers from accident, as they can be 
fed either from the boiler feed-pumps, circulating, independent, 
donkey, or bilge pumps. 

If a tube becomes leaky in the tube-sheet, it may be made 
tight by inserting a tapering iron ferule about T l g of an inch 
larger than the inside diameter of the tube. 

If a tube splits, it may be plugged with either iron or wooden 
plugs, whichever is most convenient. Iron is best for the end 
next the furnace, while wood will answer for the smoke-box end. 

Boiler Materials. 

Boiler making now holds an important place among the mechan¬ 
ical arts. Its progress has been aided chiefly by the enormous 
growth of the steam-engiue as the prime mover, by the increased 


THE ENGINEER’S HANDY-BOOK. 


481 


facilities afforded for procuring suitable materials, and by the im¬ 
provements made in working them. Iu the early days of the 
steam-engine, boilers of copper and cast-iron were used for gener¬ 
ating steam, but they were seldom subjected to a pressure higher 
than that of the atmosphere; but when pressures of 3 to 4 or even 
7 atmospheres came into use, cast-iron was found to be unreliable 
and treacherous, for which reason it was discarded in favor of 
wrought iron , which was not employed at first, in consequence of 
the difficulty found in working it and in making steam-tight joints. 
It has, however, of late years become the material employed to 
the almost entire exclusion of all others. It has been more ex¬ 
tensively employed in the construction of steam-boilers, for the 
past thirty years, than any other material, on account of its great 
tensile strength, its ductility, power of bearing sudden and trying 
strains, trustworthy nature, the ease with which it can be welded, 
riveted, patched, or mended, and its moderate first cost, etc. 

The first quality to be sought for in boiler materials is strength. 
This does not necessarily imply the mere power to resist being 
torn asunder by a dead weight, as in a testing-machine; but the 
quality to withstand, without injury, the varying shocks and 
strains to which boilers are exposed. An inferior quality of plates 
cannot be relied upon to bear the ordeal of heating and cooling 
repeatedly, as they invariably warp and twist, showing defects of 
manufacture; more especially in the process of cold bending, when 
minute fractures often occur on the outer surface of the plates of 
stubborn or inferior qualities of iron. 

The defect most commonly revealed in working boiler-plates is 
want of lamination. This defect arises from the imperfect welding 
of the several layers which make up the thickness of the plate, and 
is usually caused by interposing sand or cinder, which has not 
been expelled by hammering or rolled out during the process of 
manufacture. This is more frequent in thick than in thin plates, 
and is sometimes very difficult to detect in cold plate, although 
often discernible in the hot. It also often happens that plates 
which are passed as quite sound, on careful external examination 
41 2 F 


482 


THE ENGINEER’S HANDY-BOOK. 


are found to be severely laminated when subjected to heating and 
hammering, and prove totally unfit for use. 

Blisters are of a similar nature, and arise from the same cause 
as lamination. Sometimes they appear as mere surface defects, 
and are of no consequence; but their appearance may be an in¬ 
dication of want of care or skill in the making of the plate, and 
should always excite suspicion. It frequently happens that these 
defects pass undetected after the closest scrutiny and test by ham¬ 
mering, but disclose themselves soon after the boiler is set to work, 
especially if the plates be exposed to sudden variations of tem¬ 
perature. In the plates over the fire-grate of an externally fired 
boiler, such a blister may prove a very serious defect, and often 
necessitates the cutting out and replacement of the sheet. Infe¬ 
rior brands of iron will rapidly show unmistakable signs of weak¬ 
ness when placed under the trying ordeal of bearing the alternate 
impingement of a fierce flame and currents of cold air. The 
rapid variations of temperature caused by the sudden and frequent 
openings of the furnace door, and passage of cold air through the 
grate-bars, will soon tell on even the best iron, but more quickly 
on that of an inferior brand. 

Characteristics of boiler-iron when broken. On breaking a 
plate or bar of wrought-iron, the fracture presents an appearance 
by which the quality of the iron may, in some measure, be deter¬ 
mined. The fracture is designated, on the one hand, as fibrous, 
tough, silky, close-grained, etc., or, on the other hand, crystalline, 
coarse, open-grained, brittle, and cold-shut. When broken sud¬ 
denly, the best qualities of plate and bar iron exhibit a fine, 
close-grained, uniform crystalline fracture, even silky, of a light 
silver color; the appearance in the harder descriptions approach¬ 
ing to that of steel. The appearance of indifferently refined and 
inferior qualities is coarser, usually of a darker color, more or less 
uneven, or open, exhibiting large facets, and approaching some 
descriptions of cast-iron. When broken gradually, good iron 
presents a well drawn out, close fibre, of light greenish hue, whilst 
inferior qualities give a shorter, more open, and darker fibre. 


483 


THE ENGINEER’S HANDY-BOOK. 

When good ductile iron is gradually torn asunder, it stretches 
to a considerable extent, causing a diminution of sectional area at 
the fractured part, which should always be compared with the 
original sectional area of the specimen in judging of the quality. 
An inferior bar or plate may bear as great a tensile strain as a 
similar specimen of superior quality ; but on comparing their frac¬ 
tured areas, it will generally appear that the latter has been drawn 
out considerably, whilst the inferior specimen, having stretched 
but little, has not sensibly diminished at the fracture. This is 
owing to the fact that good ductile iron, when sudden strains occur, 
will stretch, while badly refined will snap. Wrought-iron changes 
from fibrous to crystalline, after enduring long-continued cold 
hammering, vibration, tension, jarring, and other strains, after long 
exposure to the influence of heat, or alternate expansion and con¬ 
traction whenever it has been used for the plates of a boiler fur¬ 
nace. Even the very best plates, after from ten to twenty years’ 
use in a boiler, have frequently been found to break without 
stretching, at the same time displaying a crystalline fracture. 

It has been said that this shows that a change has taken place 
in the nature of the material, and that, from being fibrous and 
tough, it has, by some unexplained cause, become crystallized and 
brittle, or that it has lost its nature in consequence of the treat¬ 
ment it has undergone, whatever that may have been. There is 
no doubt that the strains and other causes above mentioned have 
a tendency to make good iron become brittle and liable to snap 
suddenly under the same treatment that would originally have 
torn it gradually, and to this extent a change is produced in its 
nature. This snapping, and not the fatigue of the metal, is the 
direct cause of the crystalline fracture, which is but a necessary 
consequence of the suddenness of the breaking, and not a prop¬ 
erty of the iron itself. To say it snaps readily because it has be¬ 
come crystalline is to confound the cause with the effect. It is 
erroneous to say the fibrous nature has passed out of the iron, as 
its ductility can to some extent, at least, be restored, in most 
cases, by simply heating to a bright red, and slowly cooling, the 


484 


THE ENGINEER’S HANDY-BOOK. 


iron, or, failing that, by hammering or rolling it while hot. By 
heating to redness, and suddenly cooling, a piece of wrought-iron, 
it will become liable to snap, producing the same effect as cold 
hammering. The explanation of this is not clear, and it may be 
owing to the loosening of the crystals into which the composition 
of the material ultimately resolves itself. To this cause may also 
be attributed the same tendency to snap after long-continued jar¬ 
ring or alternate expansion and contraction. 

It may be asserted, without fear of contradiction, that all boiler¬ 
plate worthy of the name is fibrous; whether its hardness makes 
it liable to snap, and, therefore, appear crystalline, depends on its 
original character and the treatment it has undergone. No fine 
iron can, however, by any treatment, except burning, be made to 
appear coarse, and the fibres of the poorest descriptions of iron 
cannot, without refining, be made to appear fine and close-grained. 
From a want of knowledge of the above facts, false opinions are 
often expressed respecting the qualities of boiler-plates. 

It is no unusual thing to find intelligent mechanics and boiler¬ 
makers expressing their opinions, at coroners’ inquests, on the 
quality of the iron in exploded boilers, without anything to base 
their opinions on except the load per square inch required to tear 
the plates asunder. They seem to forget, if the boiler be an old 
one, that the age, the position in the boiler in which the rent has 
taken place, the amount of strain to which it has been exposed, 
and all the circumstances connected with the occurrence, should 
be known in order to decide understandingly as to the quality of 
the iron. It has been shown, in numerous instances, that good duc¬ 
tile iron can be made to appear crystalline when pulled asunder 
in the testing-machine, by confining the minimum sectional area 
where fracture will occur to one point or to a very short length. 

The general conclusions with regard to boiler material, which 
may be regarded as established from experiments, observations, 
and practice, thus far seem to be, 1st, That the laws of resistance 
of the parts of boilers to the internal pressure are sufficiently 
well established; 2d, It is of the utmost importance that the ma- 


THE ENGINEER’S HANDY-BOOK. 


485 


terials employed should be of the best quality as regards strength 
and durability; and as there are but few manufacturers of boiler¬ 
plates, the inspection of materials, especially boiler-plates, should 
be made by competent persons, appointed for that purpose, at the 
place of manufacture, which inspection should extend to the 
qualities of ores and the process of manufacture, the required 
brands, stamps, or certificates being put on or authorized by the 
inspectors in person. There is much greater certainty of securing 
the best materials by an inspection of the process of working, and 
of the raw materials employed, than by an inspection of plates 
after they have been sent to market, when, judging from all exter¬ 
nal appearances, good and bad plates are not easily distinguished. 

Practical limits to the thickness of boiler-plates. — The proper 
strength of boilers, in order to enable them to withstand with 
safety the required pressure of the steam, is a matter of much 
importance as regards both life and property, and the responsi¬ 
bility of the proprietors and constructors of boilers is of so grave 
a character as to justify the devotion of a much larger space to 
this subject than is convenient in this work. The principles oil 
which the strength of the material depends may be expressed in 
a very few words, — the strength being directly as the thickness 
of the metal, and, inversely, as the diameter of the boiler. 

So long as the quality of boiler-iron remains as it is at present, 
the thickness of the plate may be practically determined within 
exceedingly narrow limits, as a good boiler must be constructed 
of plate ranging in thickness from ] to 1 an inch, as anything 
less than the former cannot be properly caulked, and any thick¬ 
ness greater than the latter is difficult to rivet without the aid of 
machinery. A thickness of -§• seems to have become the standard 
thickness for all diameters of boilers intended to sustain a high 
pressure. This, perhaps, arises from the fact that boiler-makers 
seem to be better acquainted with the practical limit to the strength 
of that thickness, because it has of late years been used more than 
any other; nevertheless, for steel, or some of the higher grades ot 
American plate, a less thickness will suffice for the same pressure. 

41* 


486 


THE ENGINEER’S ITANDY-BOOK. 


Definitions of tlie Technical Terms Applied to the 
Different Kinds of Boiler-Plate. 

C. No. 1 charcoal iron means that charcoal was the fuel em¬ 
ployed in the blast-furnace when the iron was smelted. Such iron 
is not suitable for any purpose when exposed to a high tempera¬ 
ture. Although it is frequently used for the shells of boilers, it is 
very seldom employed for furnace-sheets. 

C. H. No. I charcoal iron, commonly called flange-iron, is 
manufactured by the same process as C. No. 1, with this differ¬ 
ence, that it is reheated and hammered, which increases its com¬ 
pactness, solidity, and strength as well as its capacity for resisting 
high temperatures. C. H. No. 1 is generally called cold blast- 
iron ; the process of manufacture is as follows. The pig-metal is 
remelted and refined, or converted into wrought-iron in charcoal 
fires, the balls being hammered into blooms. These blooms are 
reheated in reverberatory furnaces, and then rolled into slabs. 
These pieces are called covers, between two of which clippings 
of boiler-plate and other wrought-iron scraps are placed, after 
which the mass is brought to welding heat and passed between 
heavy rollers. The greatest danger to be encountered in this 
process arises from the imperfect welding of the pieces. It is 
often due to the slag which remains between the coils when the 
mass is heated. Iron manufactured by this process frequently 
blisters when exposed to an intense heat. Boiler-plate should 
never be manufactured by this process, as it is generally of infe¬ 
rior quality, and always proves deceptive. The only advantage 
in making it in this manner is cheapness. C. H. No. 1 charcoal 
iron is produced by piling one slab upon another at right angles 
with each other, and exposing them to a high welding heat, after 
which they are rolled and hammered, great care being taken both 
in the selection of the material and in the rolling and hammering. 

Fire-box iron is a kind of plate manufactured exclusively for 
furnaces. It is produced in the same manner as C. H. No. 1, with 
this difference, that it is subjected to two or three more processes 


THE ENGINEER’S HANDY-BOOK. 


487 


of heating, rolling, and hammering. There are many grades of 
this kind of iron, resulting from the details of the processes which 
are customary in the different plate mills, and the care with which 
the iron is selected. The names of the different manufacturers 
furnish a better guarantee than the stock of knowledge possessed 
by the most talented experts. 

Iron produced from covers filled with iron scrap will blister, 
unless the slag is expelled by patient and careful heating, rolling, 
and hammering. Such iron, if used for fire-box plates, should be 
tested as follows. Lay the plate off with a straight-edge, and 
pencil or chalk in squares of about one foot each; then, with a 
light steel hammer, strike the surface of each square about one 
inch apart, when, if there are any defects in the iron, they will in 
all probability be made manifest by the sound. As soon as each 
square is finished, it should be cancelled, in order to prevent repe¬ 
tition. If the iron is perfect, it will give out a clear sound. 

From the foregoing, it will be seen how much depends on the 
character of the material, and the care taken in the process of man¬ 
ufacture. It is well known that in many instances the iron in dif¬ 
ferent plate mills is the same in every respect, and, while the pro¬ 
cesses through which it has passed are the same to all appearance, 
on examination it has been found that that produced by one mill 
was of an excellent quality, while that produced by another was 
of a very inferior grade. As a general rule, boiler-plate that can 
be bent at right angles, when heated to a red heat, without showing 
any cracks, may be relied upon. But the indications of superior¬ 
ity will be strengthened, if the iron can stand the test of bending 
at right angles when cold, as none but the finest grades can bear it. 

Steel boiler-plates are generally made of puddled steel, in which 
the ordinary puddling process, by means of* which wrought-iron is 
made from pig-iron, is arrested at the point required for the carbon¬ 
ization of the steel. Homogeneous steel plates are produced from 
cast-steel, which is formed by melting the finest grades of wrought- 
iron in crucibles with carbonaceous matter, after which the ingots 
are reheated and rolled into plates of the desired thickness. 



488 


THE ENGINEER’S HANDY-BOOK. 


The Buckeye Automatic Cut-Off Engine. 

The cuts on pages 489, 490, represent a front and back view of 
the Buckeye automatic cut-off steam-engine. As may be observed, 
the bed-plate is a modification of the Corliss or girder-frame pattern, 
a design which possesses sufficient rigidity, without extra weight 
of metal. It is faced up at one end to receive the cylinder, and 
at the other the main pillow-block. The cylinder contains the 
steam-ports, but not the exhaust-ports; and, as the valve-faces are 
as near the cylinder as is consistent with sufficient strength, the 
clearance is reduced to a minimum, a feature which renders the 
engine very economical in the use of steam. The cross-head is 
made in halves, is held together by bolts, and is attached to the 
piston-rod by means of a thread on the rod. The cross-head shoes 
move in flat guides, and can be easily adjusted by means of screws 
and jam-nuts. 

The main steam-valve is driven by a fixed eccentric in the usual 
manner. An adjustable eccentric, the position of which on the 
shaft is under the control of the governor, works the cut-off valves. 
A novel feature of the cut-off valve-gear is a rock-shaft working 
in a bearing in the rocker-arm belonging to the main valve-gears. 
The adjustable eccentric is attached to a pendant arm on the outer; 
end of it, and a similar but vertical arm on the inner end con¬ 
nects it to the head, and thus works the cut-off valve. The effect 
of this device is to secure a correct movement of the cut-off valves 
relatively to their seats in the moving main valve, and at the same 
time to effect a degree of adjustment of the cut-off exactly cor¬ 
responding to the degree of change in the angular position of the 
eccentric, neither of which is possible without such an arrange¬ 
ment. These engines are in very general use, and are said to be 
very durable and economical. One of them on exhibition at the 
Centennial Exposition at Philadelphia attracted considerable at¬ 
tention. They are manufactured (both condensing and non-con¬ 
densing) by the Buckeye Engine Company, Salem, Ohio, under 
J. W. Thompson’s patent. 


Front View of the Buckeye Automatic High-Pressure Cut-Off Engine. 


489 







































































































490 


the engineer’s handy-book 



i 


Back View of the Buckeye Automatic High-Pressure Cut-Off Engine. 


























































































THE ENGINEER’S HANDY-BOOK. 


491 


Questions, 

THE ANSWERS TO WHICH MAY BE FOUND IN THE TEXT. 

Define the term steam-boiler. 

* 

Why is there more need of accurate information in relation to 
the steam-boiler than to the steam-engine ? 

What causes affect the strength and durability of steam-boilers? 

What qualities are most desirable in a steam-boiler? 

\ 4 Hr ' 1 ' 

Describe the nature and effect of the destructive forces, both 
chemical and mechanical, that act on steam-boilers. 

Of what form should a boiler be constructed to embody the 
greatest strength ? 

Give the names of the different boilers in use, both land and 
marine, their advantages and disadvantages. 

State the proportion of heating-surface to grate-surface sufficient 
to constitute a horse-power in a steam-boiler. 

What conditions will influence the amount of water which one 
pound of coal will evaporate in a steam-boiler, also the maximum 
and minimum evaporation per pound of coal ? 

Give the principal causes which induce foaming in steam-boilers. 

Give the names of the different adjuncts of steam-boilers. 

Give the rule for finding the bursting-pressure of steam-boilers. 

Give the rule for finding the safe working-pressure of steam- 
boilers. 

Give the rule for finding the internal strain caused by the press¬ 
ure of steam on the shells of steam-boilers. 



492 


THE ENGINEER’S HANDY-BOOK. 


Give the rule for finding the pressure per square inch of sectional 
area on the crown-sheets of steam-boilers. 

Give the rule for finding the safe external pressure of boiler- 
flues. 

Give the rule for finding the collapsing-pressure for boiler-flues. 

Give the rule for finding the number of square feet of heating- 
surface in any given number of flues or tubes. 

Give the rule for finding the relative strength of single- and 
double-riveted seams of steam-boilers. 

Give the rule for finding the strength of stays for steam-boilers. 

Give the rule for finding the heating-surface for any steam- 
boiler. 

Explain the object of stay-bolts, their breaking-strength, etc. 

Explain the causes which induce the formation of scale in steam- 
boilers. 

Give the chemical ingredients of the scale which forms in steam- 
boilers. 

Explain the causes of the loss of fuel induced by incrustation 
in steam-boilers. 

* i ^ y 1 ^ JE 

What are the causes which induce deterioration in steam-boilers? 

f I I | O "* * } , ^ . . i 

Does the tensile strength of boiler-iron increase by the appli¬ 
cation of heat? and, if so, up to what degree Fah. does it increase? 

What are the causes of corrosion in steam-boilers? and what 
analogy does corrosion bear to combustion ? 

What advantage has mechanical firing over manual firing, and 

vice versa ? 


THE ENGINEER'S HANDY-BOOK. 


493 


Give the technical terras as applied to firing. 

Give the technical terms employed in relation to steam-boilers. 

Explain the cause of friction in riveted seams. 

What is the object of caulking? 

,'*8 1' , iUlB fi'MJI 10 9J&BW JJ.tflJ’ffl OXCfTlr JO flOljEfWOT 9nl '200(7 

Explain the causes of steam-boiler explosions. 

What is the object of a safety-valve on a steam-boiler? 

Give the pule for finding the weight necessary to be placed on 
a safety-valve lever when the area of the valve, pressure, etc., are 
given. 

Give the rule for finding the pressure per square inch against 
the safety-valve when the area of the valve, weight of ball, etc., 
are known. 

Give the pule for finding the pressure at which the safety-valve 
is weighted when the length of the lever, the weight of the ball, 
etc., are known. 

Give the pule for finding the centre of gravity of taper levers 
of safety-valves. 

Explain the comparative advantages and disadvantages of dead¬ 
weight, spring, and lock safety-valves. 

Explain the cause of draught in chimneys. 

4 

Explain the advantages and disadvantages of square, oval, and 
circular chimneys. 

Give the Pule for finding the area of a chimney or funnel neces¬ 
sary to produce a sufficient draught to consume a given quantity 
of fuel in a given time. 

What ape the advantages of superheaters? 

42 


494 the engineer’s handy-book. 

What is the object of an interceptor? 

What are the chemical ingredients which constitute smoke? 

Can smoke, when once formed, be consumed by any mechanical 

process ? 

Does the formation of smoke incur a waste of fuel, and, if so, 
to what extent? 

Explain the meaning of the technical terms applied to the dif¬ 
ferent adjuncts of steam-boilers. 

What course should an engineer or fireman pursue when first 
entering the boiler-room in the morning ? 

What precaution should be taken before starting a fire under 
a boiler? 

What course should an engineer adopt on taking charge of an 
engine and boiler for the first time? 

How should the fire be regulated when first started under a 
boiler ? 

Under what conditions should a boiler be blown out? 

What should be the condition of a boiler when it is to be filled 
with cold water? 

What course should be adopted with boilers before cleaning? 

How should boilers be treated when a forced draught is used? 

How should the pressure in a boiler be regulated ? 

How should the kindling material be placed on the grate pre¬ 
paratory to starting a fire ? 

How often should steam-boilers be cleaned ? 


THE ENGINEER’S HANDY-BOOK. 495 

Should the cleaning of boilers be neglected, when solvents are 
used for the prevention and removal of scale? 

What precautions should be taken before new boilers are put 
into service ? 

How often should the flues or tubes of boilers be cleaned ? 

What course should be adopted in case the water in a boiler 
becomes dangerously low ? 

What course should be pursued in case the water-supply should 
become interrupted for any length of time ? 

What precaution should an engineer take, in case it becomes 
necessary to blow out a certain quantity of water every day? 

How should the supply of feed-water be regulated ? 

What advantages are gained by filling marine-boilers with salt¬ 
water for the first time ? 

What is the meaning of the term “salting” when applied to 
marine-boilers? 

What parts of any class of steam-boilers are most likely to suf¬ 
fer from the effects of heat ? 

What is the most practical method to adopt in case a boiler- 
tube should become leaky ? 

What course should an engineer or fireman adopt in case a 
tube should become split? 

Give the characteristics of good boiler material, whether iron, 
steel, or copper. 

Give the definitions of the technical terms applied to the dif¬ 
ferent kinds of boiler-plates. 


496 


THE ENGINEER^ HANDY-BOOK. 


PART SEVENTH. 


Air. 

The atmosphere is known to extend at least 45 miles above tbe 
earth. Its aggregate weight has been calculated at upwards of 
77,000,000,000 of tons, or equivalent to the weight of a solid globe 
of lead 60 miles in diameter. Hence, this enormous weight re¬ 
poses incessantly upon the earth’s surface, and upon every object, 
animate or inanimate, solid, liquid, or aeriform. 100 cubic inches 
of air at the surface of the earth, when the barometer stands at 
34 inches, and at a temperature of 60° Fah., weigh about 31 grains, 
being thus about 815 times lighter than water, and 11,065 times 
lighter than mercury. The component parts of the air are about 
79 measures of nitrogen gas and 21 of oxygen ; or, in other words, 
air consists of (by volume) oxygen, 21 parts ; nitrogen, 79 parts 
(by weight); oxygen, 77 parts; nitrogen, 23 parts. 

Now, since the air is possessed of weight, it must be evident 
that a cubic foot of air at the surface of the earth has to support 
the weight of all the air directly above it; and that, therefore, the 
higher we ascend in the atmosphere, the lighter will be the cubic 
foot of air; or, in other words, the farther from the surface of the 
earth the less will be the density of the air. At the height of 
three and a half miles, it is known that the atmospheric air is only 
half as dense as it is at the surface of the earth. From the nature 
of fluids, it follows that the atmosphere presses against any body 
with which it comes in contact — because fluids exert a pressure in 
all directions — upwards, downwards, sidewise, and obliquely. Its 
particles are so inconceivably minute, that they enter all substances, 
even liquids. It penetrates all the ramifications and innermost 
recesses of porous bodies, and is mixed up with and circulates in 
the blood of men and animals; and by the pressure of its super¬ 
incumbent strata, it is urged through almost every substance. It 



497 


THE ENGINEER’S HANDY-BOOK. 

is this circulation through the interior of the bodies of men and 
animals which counterbalances its outer pressure; because, if its 
weight were not neutralized, neither man nor beast could walk, 
and would be as mute as statues of lead, and lips once closed could 
never again be opened. 

The amount of pressure of a column of air, whose base is one 
square foot and whose altitude is the height of the atmosphere, 
has been found to be 2156 pounds avoirdupois, or very nearly 15 
pounds of pressure on every square inch. Consequently, it is com¬ 
mon to state the pressure of the atmosphere as equal to 15 pounds 
on the square inch. If any other gaseous body or vapor — such as 
steam — exerts a pressure equivalent to 15 pounds on the square 
inch, then the force of that vapor is said to be equal to one atmos¬ 
phere. If the vapor be equal to 30 pounds on every square inch, 
then it is equal to two atmospheres, and so on; consequently, the 
atmospheric pressure is capable of supporting about 30 inches of 
mercury, or a column of water 34 feet high. 

It is known that the pressure of the atmosphere is not constant, 
even at the same place. At the equator, the pressure is nearly 
constant, but is subject to great changes in high latitudes. In 
some countries the pressure of the atmosphere varies so much as 
to support a column of mercury so low as 28 inches, and at other 
times so high as 31, the mean being 29'5 ; thus making the average 
pressure between 14 and 15 pounds on the square inch. But in 
scientific books, generally, the pressure is understood, in round 
numbers, to be 15 pounds; so that a pressure exerted equal to 1, 
2, 3, 4, etc., atmospheres means such a pressure as would support 
30, 60, 90, 120, etc., inches in a perpendicular column, or 15, 30, 
45, 60, etc., pounds on every square inch. 

The pressure of the air differs at different altitudes; * at 7 miles 
above the surface of the earth, the air is four times lighter than 
it is at the surface; at 14 miles it is 16 times lighter; and at 21 
miles it is 64 times lighter. It requires 13,817 cubic feet of air 


* See table on page 498. 
2G 


42 * 




498 


THE ENGINEER’S HANDY-BOOK, 

to make one pound; consequently, one cubic foot of air at the 
surface of the earth weighs 527 grains, or £ of an ounce avoir¬ 
dupois ; but under a pressure of 54 tons to the square inch, air 
becomes as dense, and would weigh as much per cubic foot, as 
water. 

TABLE 


OF ALTITUDES ABOVE SEA-LEVEL, AND THE CORRESPONDING ATMOS¬ 
PHERIC PRESSURES, DEDUCED FROM THE OBSERVATIONS OF THE HAY¬ 
DEN EXPEDITION TO THE ROCKY MOUNTAINS. 


Location. 

Altitude 
in Feet. 

Pressure 

OF THE 

Atmosphere. 

Altoona, Pa. ..... 

1,168* 

14*08 

Cairo, Ill....... 

291-23 

14-56 

Cheyenne, Wy. Ter..... 

6,075-28 

11-48 

Cincinnati, 0. . 

440- 

14-46 

Cresson, Pa. 

2,000- 

1364 

Denver, Col. 

5,196*58 

11-94 

Golden City, Col. 

5,728-98 

11-67 

Lake Champlain .... 

100-84 

14-64 

“ Erie. 

573-08 

14-39 

“ Huron ..... 

589-99 

14-38 

“ Michigan. .... 

589-15 

14-39 

“ Ontario. 

249-99 

14-56 

Louisville, Ky. .... 

404- 

14-48 

Mt. Lincoln, Col. .... 

14,296-66 

7-06 

New Albany, Ind. .... 

379-75 

14-5 

Ogden, Utah ..... 

4,303-3 

12-42 

Omaha, Neb. ..... 

977-9 

14-18 

Pike’s Peak, Col. .... 

14,148-66 

71 

Pittsburg, Pa. ..... 

699-2 

14-33 

Rock Island, Ill. .... 

566-68 

14-40 

St. Louis, Mo. 

429-29 

14-17 

Terre Haute, Ind. .... 

485-55 

14-44 













THE ENGINEER’S HANDY-BOOK. 


499 


TABLE 

SHOWING THE FORCE OF THE WIND IN POUNDS PER SQUARE FOOT AT 

DIFFERENT VELOCITIES. 


Miles 

per 

Hour. 

Feet per 
Second. 

Force per 
Square Foot 
Pound. 

1 

1-47 

0-005 

2 

2*93 

0-020 

3 

4-4 

0-044 

4 

5-87 

0-079 

5 

7*33 

0-123 

6 

8*8 

0-177 

7 

1025 

0-241 

8 

11-75 v 

0-315 

9 

13-2 

0-400 

10 

14-67 

0-492 

12 

17-6 

0-708 

14 

20-5 

0-964 

15 

22-00 

1-107 

16 

23*45 

1-25 

18 

26-4 

1-55 

20 

29-34 

1-968 

25 

36-67 

3-075 

30 

44-01 

4-429 

35 

51-34 

6-027 

40 

58-68 

7-873 

45 

66-01 

9-963 

50 

73-35 

12-30 

55 

80-7 

14-9 

60 

88-02 

17-71 

65 

95-4 

20-85 

70 

102-5 

24-1 

75 

no- 

27-7 

80 

117-36 

31-49 

100 

146-66 

50- 


! 


Hardly perceptible. 
Just perceptible. 


* Gentle, pleasant wind. 


^Pleasant, brisk gales. 


Very brisk. 

High wind. 

Very high. 

Storm or tempest. 
Great storm. 
Hurricane. 
Tornado. 


Horse-Power of Wind Storms. 

It is asserted that severe wind storms exert a pressure of from 
25 to 30 lbs. per square foot, and travel from 50 to 70 miles per 





















500 


THE ENGINEER’S HANDY-BOOK. 


hour. Assuming that the pressure is 30 lbs. per square foot, or 

of a pound per square inch, with a speed of 66 miles per hour, 
theu, as there are 27,878,400 square feet, or 4,014,489,600 square 
inches in a square mile, if the pressure of the storm was exerted 
for the height of half a mile, it will give an area of 2,007,244,800 
square inches for each mile in width upon which the storm acts. 

Rule for finding the horse-power of wind storms. 

Multiply the area acted on in inches by the pressure in lbs. per 
square inch; then multiply this product by the speed in feet per 
minute, and divide by 33,000. The quotient will be the horse¬ 
power of the storm. 

Example. — 2,007,244,800 square inches x 1’5 lbs. pressure X 
5800 feet -r- 33,000, which gives as a result 70,557,700 horse¬ 
power developed for each mile of breadth of the track of the storm. 
To produce the same horse-power with improved engines consum¬ 
ing but two pounds of coal per hour per horse-power, would re¬ 
quire 63,000 gross tons of coal. 

Altitude of the Highest Mountains in the World. 

The highest peak of the Himalayas, in Asia, is 25,659 feet 

above sea-level. 

Mont Blanc, the highest peak of the Alps, is 15,732 feet. 

The highest peak of the Andes is 14,760 feet. 

The peak of Teneriffe is 11,454 feet. 

Mount >^tna is 9,000 feet. 

The highest point in the Pyrenees is 8,400 feet. 

The highest inhabitable point on the globe is Ancomarsa, one 
of the Peruvian Andes, which is 16,000 feet. 

Highest Waterfalls in the World. 

The Ribbon Falls, Yosemite Valley, U. S. A., 3,300 feet. 

Yosemite Falls, U. S. A., 2,600 feet. 

The Arve Falls, Bavaria, Europe, 2,000 feet. 

The Falls of Montmorency, Canada, 250 feet. 

Niagara Falls, United States, 158 feet. 


501 


THE ENGINEER’S HANDY-BOOK. 

TABLE 


SHOWING THE RELATIVE VOLUMES OF AIR AT VARIOUS TEMPERATURES. 


Temp. 

Fah. 

Volume in 
Cubic In. 

Temp. 

Fah. 

Volume in 
Cubic In. 

Temp. 

Fah. 

Volume in 
Cubic In. 

Temp. 

Fah. 

Volume in 
Cubic In. 

—49 

834*7 

— 6 

922*5 

37 

1010*2 

80 

1098-0 

—48 

836*7 

— 5 

924-5 

38 

1012*2 

81 

1099-0 

—47 

838*8 

— 4 

926*5 

39 

1014*3 

82 

noo-o 

—46 

840-8 

— 3 

928-6 

40 

1016*3 

83 

1102-1 

—45 

842*8 

— 2 

930*6 

41 

1018*4 

84 

1104*1 

—44 

844*9 

— 1 

932*7 

42 

1020*4 

85 

1106*2 

—43 

8 46*9 

— 0 

934-7 

43 

1022*4 

86 

1108*2 

—42 

849*0 

1 

936-7 

44 

1024*5 

87 

1110*2 

—41 

851*0 

2 

938-8. 

45 

1026-5 

88 

1112*3 

—40 

853*1 

3 

940-8 

46 

1028-6 

89 

1114-3 

—39 

855*1 

4 

942-9 

47 

1030*6 

90 

1116*4 

—38 

857-1 

5 

944*9 

48 

1032*7 

91 

1118*4 

—37 

859*2 

6 

947-0 

49 

1034-7 

92 

1120*4 

—36 

861*2 

7 

949-0 

50 

1036-7 

93 

1122-5 

—35 

863*3 

8 

951-0 

51 

1038*8 

94 

1126*5 

—34 

865*3 

9 

953*1 

52 

1040-8 

95 

1128*6 

—33 

867*3 

10 

955*1 

53 

1042*9 

96 

1130*6 

—32 

869’4 

11 

957-1 

54 

1044*9 

97 

1132-7 

—31 

871-4 

12 

959*2 

55 

1046-9 

98 

1134-7 

—30 

873-5 

13 

961-2 

56 

1049-0 

99 

1136-7 

—29 

875-5 

14 

963*3 

57 

1051*0 

100 

1138-8 

—28 

877-6 

15 

965*3 

58 

1053*1 

101 

1140*8 

—27 

879*6 

16 

967*3 

59 

1055*1 

102 

1142-9 

—26 

881*6 

17 

969*4 

60 

1057*1 

103 

1144*9 

—25 

883-7 

18 

971-4 

61 

1059*2 

104 

1147-0 

—24 

885-7 

19 

973*5 

62 

1061-2 

105 

1149-0 

—23 

887*8 

20 

975*5 

63 

1063-3 

106 

1151 -0 

—22 

889-8 

21 

977*6 

64 

1065-3 

107 

1153-1 

—21 

891-8 

22 

979*6 

65 

1067-3 

108 

1155-1 

—20 

893*9 

23 

981*6 

66 

1069-4 

109 

1157-1 

—19 

895-9 

24 

983-7 

67 

1071*4 

110 

1159-2 

—18 

898*0 

25 

985-7 

68 

1073-5 

111 

1161-2 

—17 

'9000 

26 

987*8 

69 

1075*5 

112 

1163-3 

—16 

902-0 

27 

989*8 

70 

1077-6 

113 

1165-3 

—15 

904-1 

28 

991*8 

71 

1079*6 

114 

1167-3 

—14 

906-1 

29 

993*9 

72 

1081-6 

115 

1169-4 

—13 

908*2 

30 

995*9 

73 

1083-7 

116 

1171-4 

—12 

910*2 

31 

998-0 

74 

1085-7 

117 

1173-5 

—11 

912*2 

32 

1000*0 

75 

1087*8 

118 

1175-5 

—10 

914*3 

33 

1000-2 

76 

1089-8 

119 

1177-6 

— 9 

916*3 

34 

1004-1 

77 

1091-8 

120 

1179*6 

— 8 

918*4 

35 

1006*1 

78 

1093-9 

121 

1181-6 

— 7 

920*4 

36 

1008-2 

79 

1095-9 

122 

1183-7 


























502 


THE ENGINEER’S HANDY-BOOK 


TABLE — [Continued.) 


Teinp. 

Fah. 

Volume in 
Cubic In. 

Temp. 

Fah. 

Volume in 
Cubic In. 

Temp. 

Fah. 

Volume in 
Cubic In. 

Temp. 

Fah. 

Volume in 
Cubic In. 

123 

1185*7 

152 

1244-9 

180 

1302-0 

208 

1359-2 

124 

1187-8 

153 

1246-9 

181 

1304-1 

209 

1361-2 

125 

1189-8 

154 

1249-0 

182 

1306-1 

210 

1363-3 

126 

1191-8 

155 

1251-0 

183 

1308-2 

211 

1365*3 

127 

1193-9 

156 

1253-0 

184 

1310-2 

212 

1367-3 

128 

1195*9 

157 

1255-1 

185 

1312-2 

213 

1369-4 

129 

1198-0 

158 

1257-1 

186 

1314-3 

214 

1371-4 

130 

1200-0 

159 

1259*2 

187 

1316-3 

215 

1373-5 

131 

1202*0 

160 

1261-2 

188 

1318-4 

216 

1375-5 

132 

1204-1 

161 

1263-3 

189 

1320-4 

217 

1377-5 

133 

1206-1 

162 

1265-3 

190 

1322-4 

218 

1379*6 

134 

1208*2 

163 

1267-3 

191 

1324-5 

219 

1381-6 

135 

1210-2 

164 

1269-4 

192 

1326-5 

220 

1383-7 

136 

1212-2 

165 

1271*4 

193 

1328-6 

230 

1404-1 

137 

1214-3 

166 

1273-5 

194 

1330-6 

240 

1424-5 

138 

1216-3 

167 

1275-5 

195 

1332-6 

250 

1444-9 

139 

1218-4 

168 

1277-5 

196 

1334-7 

260 

1465-3 

140 

1220-4 

169 

1279-6 

197 

1336-7 

270 

1485-7 

141 

1222*4 

170 

1281-6 

198 

1338-8 

280 

1506-1 

142 

1224-5 

171 

1283-7 

199 

1340*8 

290 

1526*5 

143 

1226-5 

172 

1285-7 

200 

1342-9 

350 

1546-9 

144 

1228-6 

173 

1287-8 

201 

1344-9 

400 

1751-0 

145 

1230*6 

174 

1289-8 

202 

1346*9 

500 

1955-1 

146 

1232-7 

175 

1291*8 

203 

1349*0 

600 

2159*2 

147 

1234*7 

176 

1293-9 

204 

1351-0 

700 

2363-3 

148 

1236-7 

177 

1295-9 

205 

1353-1 

800 

2567-4 

149 

1238-8 

178 

1298-0 

206 

1355-1 

900 

2771-5 

150 

151 

1240-8 

1 1242-9 

179 

1300-0 

207 

1357-1 

1000 

2975-6 


Technical Terms which are Applied to Fluids .and Vapors, 
and which Bear a Certain Relation to the Steam-Engine. 

Vaporization. —Vaporization is the act or process of vaporizing 
liquids, or converting them into vapor. 

Diffusion of vapor. — Diffusion of vapor means the state of 
being scattered, as steam on escaping from the mouth of an ex¬ 
haust-pipe is wafted away and scattered over a great extent of 
space. 






































THE ENGINEER’S HANDY-BOOK. 


503 


Compressibility means the quality of being compressible or 
being capable of being compressed into a smaller space, while in¬ 
compressibility implies the opposite property. 

Conductibility means the quality of being conductible, that is, 
of being capable of being conducted or conveyed away. 

Expansion means the state of being expanded or being capable 
of expanding, either in surface or bulk. 

Boiling-point means the temperature at which fresh water will 
boil at sea-level, which is generally understood to be 212° Fah. 

Ebullition is the motion produced in a liquid by the rapid con¬ 
version of a part of it into vapor by the application of heat. 

Condensation means the process of converting vapors into fluids 
by the abstraction of a portion of their heat mechanically. 

Evaporation is a term applied to all bodies existing in an aeri¬ 
form state; while spontaneous evaporation means the natural ten¬ 
dency inherent in all fluids to evaporate. 

Fuel. 

The word fuel is used to denote substances which may be burned 
by means of atmospheric air with sufficient rapidity to evolve heat 
capable of being applied to economical purposes. Fuel consists 
either of vegetable matter or of the products of the natural or 
artificial decomposition of such matter. Vegetable matter, which 
consists principally of woody tissue, is composed of carbon, hy¬ 
drogen and oxygen, comprising the organic part, and a small pro¬ 
portion of so-called earthy matter, that which is inorganic. The 
sun is the source of the heat-producing power of fuel, since the 
organic parts are derived from water, and, except in particular 
cases, from the carbonic acid of the atmosphere, which are decom¬ 
posed in the economy of plants by the action of solar light. 


504 


THE ENGINEER’S HANDY-BOOK. 


Hydrogen in fuel must always be in association with carbon, but 
carbon practically free from hydrogen may be procured abun¬ 
dantly and applied as fuel. In all fuel containing carbon, hydrogen, 
and oxygen, the proportion of hydrogen may be equal to or greater, 
but never less, than that required to form water with the oxygen. 
It is only the hydrogen in excess of this which is available as a 
source of heat, so that, in the combustion of a substance whose 
composition is represented by carbon and water, the carbon alone 
is the source of heat. The hydrogen existing in combination with 
oxygen in the state of water, so far from contributing to the actual 
amount of heat produced, must be evaporated at the expense of 
the heat developed by the combustion of the carbon. 

If we compare different fuels, and assign them a value for heat¬ 
ing purposes based on their chemical constitution, we will find 
that petroleum is about 25 per cent, superior to all others theoret¬ 
ically ; in round numbers, it is capable of evaporating 15 lbs. of 
water per pound of fuel, while a pound of anthracite coal can 
evaporate 11 lbs., and a pound of coke only about 9 lbs.; these 
figures varying, to a certain extent, with the different qualities of 
the fuels. 

The chemical properties of coal are, free carbon, hydro-carbons, 
water or oxygen, and hydrogen, with solid matter termed ash ; the 
proportions of these vary considerably. In some instances, the 
solid matter is 25 per cent., while with superior coal, only 6 or 10 
per cent. The products of combustion are carbonic acid gas, ni¬ 
trogen, air, ashes, and steam. 

The oxygen necessary for the combustion of coal is derived 
from the atmosphere. One pound of carbon in combustion unites 
with 2'66 lbs. of oxygen, and the product is 3*66 lbs. of carbonic 
acid gas. From the above it will be seen that to the 2*66 lbs. 
of oxygen 11 lbs. of air would have to be brought into contact 
with the pound of coal (if pure carbon) to render its combustion 
complete; but, as coal contains hydrogen, it is found that instead 
of 11, 12 lbs. are required. 

The value of wood as fuel compared with coal. — Two and a 


THE ENGINEER’S HANDY-BOOK. 505 

half pounds of dry wood are equal to one pound (average quality) 
of soft coal, and the fuel value of the same weight of different 
woods is very nearly the same, — that is, a pound of hickory is 
worth no more for fuel than a pound of pine, assuming both to 
be dry. If the value be measured by the weight, it is important 
that the wood be dry, as each 10 per cent, of moisture or water 
in the wood will detract about 12 per cent, from its value as a 
fuel. 

The weight of one cord of different woods (air-dried) is as 


follows: 

Hickory, or Hard Maple.. 4500 lbs. 

White Oak ........ 3850 “ 

Beech, Red Oak, and Black Oak .... 3250 “ 

Poplar, Chestnut, and Elm ..... 2350 “ 

Pine .. 2000 “ 


The fuel value of wood, as compared with coal, is about as 
follows: 

1 Cord air-dried Hickory, or Hard Maple, equal to 2000 lbs. coal. 
1 Cord air-dried White Oak equal to . . . 1725 “ “ 

1 Cord air-dried Beech, Red Oak, or Black Oak 

equal to . . . . . . . . 1450 “ “ 

1 Cord air-dried Poplar, Chestnut, or Elm equal to 1050 “ 

1 Cord air-dried Average of Pine Wood equal to 925 “ 

Comparative value of different kinds of wood for fuel. 


Shellbark Hickory . . 

. 100 

Yellow Oak . . 

• • • 

60 

Pignut Hickory . . . 

. 95 

Hard Maple . . 

• • • 

59 

White Oak .... 

. 84 

White Elm . . 

• • • 

58 

White Ash . . . . 

. 77 

Red Cedar. . . 

• • • 

56 

Dog-W ood. 

. 75 

Wild Cherry . . 

• • • • 

55 

Scrub Oak. 

. 73 

Yellow Pine . . 

• • • 

54 

White Hazel .... 

. 72 

Chestnut . . . 

• • • 

52 

Apple-Tree .... 

. 70 

Yellow Poplar . 

• • • 

51 

Red Oak. 

. 67 

Butternut and 

White 


White Beech .... 

. 65 

Birch.... 


43 

Black Birch .... 

. 62 

White Pine . . 

• • • 

30 


43 

















506 


THE ENGINEER’S HANDY-BOOK. 


Fire. — Fire is one of the oldest chemical phenomena. Its dis¬ 
covery was one of the greatest boons conferred on mankind, as 
with it arose sociability, the family joys of the domestic hearth, 
all industries and arts, together with the wonders they have pro¬ 
duced, and still produce from day to day. Hence, we can readily 
understand how it is that fire has ever been, and still is, among 
nations the object of a special worship (priests of Baal, Gebers, 
Hindoos, Brahmans, etc.), and has often figured in the religious 
or funereal rites of nations most remote from each other, both 
in time and space, as the Chaldees, Hebrews, Greeks, Romans, 
Peruvians, Mexicans, etc. But how and when this great discovery 
was made, in the absence of which we can hardly conceive of the 
possibility of human arts, or even of human existence, is un¬ 
known. 

Flame. — Flame is gas or vapor, of which the surface, in con¬ 
tact with the atmospheric air, or other supporter of combustion, 
burns with the emission of light. The luminosity of flame is 
generally admitted to be caused by the presence of particles of 
solid matter within, or in immediate contact with, the gas in active 
combustion. 

Smoke. — Smoke is the product of imperfect combustion, caused 
either by a want of oxygen or a want of temperature. Bitu¬ 
minous coal contains from 5 to 6 per cent, of hydrogen, which 
unites with the oxygen necessary to combustion, and constitutes 
water. A ton of bituminous coal will make nearly one-third of 
a ton of water in the form of steam. That this steam is black, 
does not necessarily indicate the presence of much carbon, as a 
grain of soot, it distributed evenly in fine particles through a 
cubic foot of steam, would color it blacker than the ace of spades. 

Chemical analysis proves the basis of soft coal to be carburetted 
hydrogen, but it generally contains benzole, naphtha, asphaltum, 
paraffine, lubricating oil, and a great variety of other substances 
used in the mechanical arts. 


THE ENGINEER’S HANDY-BOOK. 


507 


Heat. 

According to the dynamical or mechanical theory, heat is the 
result of motion among the atoms of matter, or, as it may be 
otherwise stated, of inter-atomic movement; and this motion is 
capable of being propagated through space, from one body to 
another, by undulations of a so-called ether assumed to be every¬ 
where existent in the universe. 

The relative effect of such heat producing motion, or, in other 
words, the relative proportions of heat required to cause given 
effects, may be accurately indicated by numbers, just as if heat 
were a ponderable agent; and it is usual to speak of heat as if it 
were an independent material substance : thus, it is said to be 
evolved, or emitted, radiated, conducted, absorbed, and stored up, 
or accumulated. -As a variable amount of the heat evolved in 
the combustion of a body is absorbed in the work of effecting 
alterations in the physical condition of the combustible elements 
necessary to their effective oxidation, it is impossible to estimate 
the absolute quantity of heat evolved by the combustion of a 
body; yet the relative quantities of heat evolved by the com¬ 
bustion of different bodies which may be utilized, can be accurately 
determined. 

One of the remarkable effects of the application of heat to 
matter is, that the same amount will affect equal weights of dis¬ 
similar kinds in different degrees. Thus, the amount of heat that 
will raise 1 lb. of water from 100° to 200° Fah, will raise 30 lbs. 
of mercury through the same range. The amount that will raise 
1 lb. of water 1°, will raise 14 lbs. of air. 

The capacity of a body for heat is termed its specific heat , and 
may be defined as the number of units of heat necessary to raise 
the temperature of 1 lb. of that body 1° Fah. 

The thermal unit, or unit of heat, as it is termed, is the quan¬ 
tity of heat that will raise 1 lb. of pure water 1° Fah., or from 
39° to 40° Fah. 

The term latent heat means the quantity of heat which has dis- 



508 


THE ENGINEER’S HANDY-BOOK 


appeared from a body, owing to an increase of temperature. The 
sensible heat is that which is sensible to the touch or measurable 
by the thermometer. 

The mechanical equivalent of heat is the amount of work per¬ 
formed by the conversion of one unit of heat into work, and the 
mechanical theory of heat is based on the assumption that heat and 
work are mutually convertible. 

TABLE 


SHOWING THE LATENT HEAT OF VARIOUS SUBSTANCES. 


Ice . 




Fah. 

. 140° 

Steam 




Fah. 

. 990° 

Sulphur 




. 144 

Vinegar . 




. 875 

Lead . 




. 162 

Ammonia 




. 860 

Beeswax . 




. 176 

Alcohol . 




. 442 

Zinc . 




. 493 

Ether 




. 301 


TABLE 

SHOWING THE RADIATING PROPERTIES OF DIFFERENT SUBSTANCES. 


Water 

Fah. 

. 100° 

Blackened Tin . 


• • 

Fah. 

100° 

Lampblack 

. 100 

Clean Tin 


• • 

12 

Writing-Paper . 

. 100 

Scraped Tin 


• • 

16 

Glass 

. 90 

Ice . 


• • 

85 

India-Ink . 

. 88 

Mercury . 


• • 

20 

Bright Lead 

. 19 

Polished Iron . 


• • 

15 

Silver 

. 12 

Copper 


• • 

12 

SHOWING THE 

TABLE 

EFFECTS OF HEAT UPON DIFFERENT 

BODIES. 


Fah. 

Cast Iron thoroughly smelted 2,754° 

Lead melts at . 

« 

• • 

Fah. 

594° 

Fine Gold melts at. 

. 1,983 

Bismuth “ 

• 

• • 

476 

Fine Silver “ 

. 1,850 

Tin “ . 

• 

• • 

421 

Copper “ 

Brass “ 

. 2,160 
. 1,900 

Tin and Bismuth,' 
equal parts 

► melt at 

283 

Zinc “ 

. 740 

Alcohol boils at 

• 

• • 

174 

Quicksilver boils at 

. 630 

Ether “ 

• 

• • 

98 

Linseed Oil “ 

. 600 

Mercury melts at 

• 

• • 

39 

























509 


THE ENGINEER S HANDY-BOOK. 


TABLE 


SHOWING THE 

SPECIFIC HEAT OF DIFFERENT 

SUBSTANCES. 


SOLIDS. 


Copper .... 

. . 0-0951 

Brass. . . 

.... 0-0939 

Gold. 

. . 0 0324 

Glass . . 

.... 0T977 

Iron. 

. . 0T138 

Ice ... 

.... 0-5040 

Lead. 

. . 0-0314 

Sulphur. . 

.... 0-2020 

Platinum . . . 

. . 0-0324 

Charcoal 

.... 0-2410 

Silver .... 

. . 0-0570 

Alumina 

.... 0-1970 

Tin. 

. . 0*0562 

Stones, Bricks, etc., about 0*2200 

Zinc. 

. . 0 0955 




LIQUIDS. 


Water .... 

. . 1-0000 

Mercury. . 

.... 0-0332 

Lead (melted) 

. . 0-0402 

Alcohol . . 

.... 0 6150 

Sulphur “ . . 

. . 0-2340 

Fusel Oil . 

.... 0-5640 

Bismuth “ . . 

. . 0-0363 

Benzine . 


Tin “ . . 

. . 0-0637 

Ether . . 

.... 05034 


Hi! 


TABLE 

SHOWING THE RELATIVE WEIGHT AND VOLUME OF DIFFERENT GASES. 


Air 

Oxygen 
Hydrogen . 

Steam Gas . 
Carbonic Acid Gas 
Nitrogen 
Olefiant Gas 
Carbonic Oxide . 
Ammonia . 

43* 


0*238 . 

. 0T69 

0-218 . 

. 0-156 

3-405 . 

. 2-410 

0-480 . 

. 0-346 

0-217 . 

• ••••••• 

0-244 . 

• #••••»• 

0-404 . 

. 0T73 

0-245 . 

. 0-237 

0-508 . 

. 0-299 































510 


THE ENGINEER’S HAIDY-BOOK. 


TABLE 

SHOWING THE NON-CONDUCTING PROPERTIES OF DIFFERENT MATERIALS 

AT EVEN THICKNESS. 


Black Slate ........ 100 

Sandstone . . . . . . . . * . 71*95 

Fire-Brick. . . 61*70 

Soft Chalk . ... . . 56 

Asphaltum. .. . . . . . 45 

Oak Wood . . ... 33*66 

Pine Wood ... 27*61 

Wood and Plaster._ 25*55 

Sulphate of Lime ..... .. . 20*26 

Sulphate of Lime and Sand . ' . .... . 18*70 

Coarse Ashes, Shavings, Hay, and Straw . . '. 25-85 

Sawdust and Tan-Bark (fine) ..... 17-20 

Mineral Wood or Asbestos, cemented .... 18-20 

Fine Asbestos, in thread.13-15 

Fine-Powdered Charcoal ...... 14-16 

Ordinary Mineral Wool, Hair-Felt, Cat-Tail, etc. . 10-13 


Extra Mineral Wool, Raw Silk, Cotton, etc., quite loose 8-10 
Ice 0 

■ • ’ . I . 

Cooling of liquids and solids. —The velocities with which a 
solid body cools in a liquid are approximately the same, whether 
it be placed near the surface or near the bottom. It is slightly 
less when the body is brought immediately under the surface. 
The nature of the external surface of the cooling body has but 
little influence. The velocity of cooling increases very consider¬ 
ably for the same body immersed in the same liquid with increas¬ 
ing temperature of the latter. If the cooling power of water be 
taken at 1, that of alcohol is equal to 0*58; mercury, 2*07; sul¬ 
phate of copper, 1*03, and common salt, 1*05. 

Combustion. 

Combustion is a subject of interest to the engineer, manufac¬ 
turer, and individual, and must ever continue to be so, while the 








THE ENGINEER’S nANDY-BOOK. 511 

steam-engine is used as a motive power, and so long as artificial 
heat is employed for manufacturing and domestic purposes, as 
well as for the preservation of animal life. This subject has not 
heretofore received that consideration which its importance in an 
economical point of view so eminently deserves. This arose, in 
part, from the lavish hand with which a bountiful Nature has sup¬ 
plied us with minerals, woods, and cereals, and the close prox¬ 
imity of the source of supply to the avenue of demand ; but the 
increase of population and demand, and the diminution in supply, 
are making the examination of the subject an imperative neces¬ 
sity. It is quite common to see in the neighborhood of manu¬ 
facturing establishments, and even households, splendid lumps of 
the finest qualities of anthracite coal, nearly pure carbon, lying in 
the highway, to be forced into the ground by the pressure of hoof 
or wheel, and after rain storms dumping-grounds glisten with 
kernels of coal that have never been exposed to the fire, which 
are as fine as, and in many respects superior to, that which has been 
placed in the furnace. The same thing may be said of oil, cotton- 
waste, piston-rod packing, etc.; but, as the cost of material has to 
be paid out of the profits of production, such carelessness is gen¬ 
erally followed by retributive justice; and the old adage which 
says “ that a wilful waste is generally followed by a woeful want,” 
is sooner or later realized. 

Combustion is the result of chemical alterations of a violent 
character, and the heat thus evolved is merely an incidental phe¬ 
nomenon, or a vehement combination of various materials. In 
combustion, the carbon and oxygen have so great a chemical af¬ 
finity for each other, that they rush violently together, and by the 
force of their combustion produce instant heat. 

The composition of anthracite coal of the best quality is as 
follows: carbon, 90'45; hydrogen, 2'43; oxygen, 2*45, and ashes 
4*67, with a minute quantity of nitrogen. When coal is heated, it 
discharges its gas; the solid carbon then ignites in presence of 
oxygen, and retains the temperature necessary for combustion as 
long as the necessary quantity of oxygen is applied. The average 


512 the engineer’s handy-book. 

weight of anthracite coal is about 53 lbs. per cubic foot, and the 
number of cubic feet per ton will average about 42*3. 

Bituminous coal is a compound substance. A ton (2000 lbs.) con¬ 
tains about 1600 lbs. or 80 per cent, of carbon; 100 lbs. or 5 per 
cent, of hydrogen; and 300 lbs. or 15 per cent, of oxygen, ni¬ 
trogen, sulphur, and ashes. The weight of bituminous coal will 
average about 50 lbs. per cubic foot and 44*8 cubic feet to the 
ton, and in the process of coking it loses 35 per cent, of its orig¬ 
inal weight. 


TABLE 

SHOWING THE TOTAL HEAT OF COMBUSTION OF VARIOUS FUELS. 


Sort of Fuel. 

Equivalent 
in Pure 
Carbon. 

Lbs. of Water 
Evaporated 
from 212° Fah. 

Lbs, of Water 
Kaised 

1° Fah. 

Anthracite coal . 

1-05 

15-75 

15225 

Bituminous “ . 

1-06 

15-90 

15370 

Coke .... 

0*94 

1400 

13620 

Charcoal . . . 

0-93 

14-00 

13500 

Dry wood. . . 

0-50 

7-50 

7000 


Spontaneous combustion. — This mysterious phenomenon has 
attracted at different times the attention of chemists and philos¬ 
ophers, and many theories have been advanced to account for its 
development. Galletly, who investigated the subject, found that 
cotton-waste soaked in boiled linseed-oil, and wrung out, if exposed 
to a temperature of 170°, set up oxidation so rapidly as to cause 
actual combustion in 105 minutes. Coleman also instituted a very 
extensive series of experiments upon fragments of cotton, linen, 
jute, and woollen waste saturated with oils of different natures. 

The theory which attributes spontaneous combustion to the 
presence of pyrites in the coal, may partially account for the 
increased number of fires; but Richter has shown that, for va¬ 
rious coals experimented upon, those which contained the most 












THE ENGINEERS HANDY-BOOK. 


513 


pyrites were not the most subject to spontaneous combustion. 
According to him, air is rapidly absorbed by the coal, and the 
oxygen ot the air then combines with the organic components to 
produce carbonic acid and develop heat. According to all prob¬ 
abilities, however, the heat which determined the spontaneous 
combustion is due both to the oxidation of the iron and to that 
of the carbonized matters. This confined in badly-ventilated holds 
speedily reaches a temperature sufficiently high to produce com¬ 
bustion. 

That most of the bituminous coals (English and American) are 
subject to spontaneous combustion when in bulk, and under favor¬ 
able circumstances, has long been known. Experiments by Green- 
araann have also proved conclusively that an exposure of bitu¬ 
minous coal in heaps to the action of the weather for a period 
varying from two weeks to a year results in a large percentage of 
loss. This loss is in the nature of a slow or incomplete combus¬ 
tion ; it is greater and more rapid in large heaps than in small, 
and is also favored by the greater or less state of subdivision of 
the coal, large fragments losing proportionably less than smaller 
ones. The loss varies from 5 to 25 per cent. 

The higher the temperature the more rapid is the combustion. 
The heat around the coal-bunkers of steamships must necessarily 
be very great, from their close proximity to the boilers and fur¬ 
naces ; and in sailing-ships containing large quantities of these 
coals in bulk, taken on board mostly wet, the generation of heat 
to the point of ignition seems to be only a question of time. The 
sulphur and volatile matter in bituminous and hydrogenous coals 
are the active agents in spontaneous combustion, and the finer the 
particles the more favorable is the condition for producing that 
result. The large number of disasters, which have occurred from 
the spontaneous combustion of bituminous coals on board of steam¬ 
ships and sailing-vessels, has called public attention to the matter. 
Although the manner bv which bituminous coal stored in vessels 
becomes ignited is not yet determined, it has been demonstrated 
that the conditions for the work of spontaneous combustion exist 

2 II 




514 


THE ENGINEER’S HANDY-BOOK. 

wherever large bodies of bituminous coal are stored in close com¬ 
partments. 

From the foregoing considerations, it would seem that, when 
spontaneous combustion takes place among coals or other sub¬ 
stances, drowning out with water is not always effective ; as, though 
it extinguishes the fire, it leaves in the coal a condition of things 
very favorable to a renewed ignition at any moment. A terrible 
explosion of coal-gas recently occurred on board of a steamship in 
Liverpool, by which fourteen men were injured, some of them 
seriously, in consequence of a quantity of wet coal having been 
placed in the bunkers and the hatches closed. 


Water. 

Water, with the barometer at 30°, boils in the open air, at sea- 
level, at 212° Fah.; and in vacuum, at 88° Fah. The less the 
pressure of the atmosphere, the lower is the temperature at which 
water will boil. The pressure of the atmosphere at sea-level is 
14*7 lbs. per square inch, pressing equally and in all directions. 
This has been ascertained from the following illustration. Because 
the height of a column of air of one square inch area exactly 
balances a column of mercury of the same area 30 inches in 
height, and also a column of water 33*86 feet in height, it follows 
that a column of air, 30 inches of mercury, and 33*86 feet of water 
weigh the same, and since the last two weigh respectively 14*7 
lbs. per square inch, a full column of air must weigh the same. 
A cubic foot of water evaporated under a pressure of one atmos¬ 
phere, or 15 lbs. per square inch, occupies a space of 1700 cubic 
feet. 

Salt water boils at a higher temperature than fresh, owing to its 
greater density, and because the boiling-point of water is increased 
by any substance that enters into chemical combination with it. 
Mud and other substances, so long as they are kept in mechanical 
solution, will not increase the boiling-point of water; when these 
substances settle, and burn to the interior of the boilers, the boil- 


THE ENGINEER’S HANDY-BOOK. 


515 


ing-point will be increased. The density of water decreases as the 
temperature increases, since heat destroys cohesion and expands 
the particles, causing them to occupy greater space. The power 
of water to hold chemical substances, such as salts of lime, in solu¬ 
tion, decreases as the temperature increases; from this it follows 
that boilers carrying high-pressure steam form more scale than 
those working at low temperatures. 

The law of expansion by heat and contraction by cold is true 
as relating to water, with this exception, that, as hot water cools 
down from the boiling-point, it contracts until 45° Fah. is reached, 
but if cooled down from this point it expands again. The density 
of water decreases as the temperature increases, because water is 
expanded into a greater space by an increase of temperature. The 
cohesive attraction of the particles is not so great, and the water 
is therefore less buoyant, thus allowing the hydrometer to sink 
lower than it should. 

Water, like all liquids, expands by the application of heat, and 
this fact alone shows the fallacy of the commonly accepted notion 
that it is incompressible; the dilation and contraction of the liquid 
is simply extension and compression of its particles. Although 
the expansion of water is comparatively slight between its boiling 
and freezing' points, yet it is the most irregular of all liquids; so 
irregular, in fact, that it has been found impossible to find a single 
empirical formula to express the expansion at different tempera¬ 
tures. Below 50° Fah. it is more irregular than above that point, 
as water possesses what no other liquid has been discovered to 
have, and that is a point of maximum density. 

If we take a water thermometer and expose it to the cold, we 
shall observe the following curious phenomenon. The liquid will 
gradually descend until it reaches the temperature of 39*2° Fah.; 
at this point the contraction will cease; and, although the cold 
acting on the bulb is far below this point, the liquid will gradually 
ascend until it reaches 32° Fall., or freezing point, when it will 
solidify. The point at which the liquid commences to ascend is 
called its “ point of maximum density.” 


516 


THE ENGINEER’S HANDY-BOOK. 


One of the most curious phenomena connected with water 

before and after freezing, may be demonstrated as follows: Take a 
tall jar and till it with water, say at 60° Fah.; at the top of the 
jar fix a small mercurial thermometer, and another one at the 
bottom ; then place the jar at rest, exposed to the cold. The lower 
thermometer will be observed to fall more rapidly than the top 
one, until it reaches 39 , 2 3 Fah., when it will remain stationary. 
The top thermometer will now fall, and continue to do so until 
the water freezes; the bottom thermometer still remaining at 39*2° 
Fah. These effects are easily explained: the particles of water 
at the top being exposed to the cold, decrease in temperature, thus 
becoming denser, and fall to the bottom, their places being taken 
up by warmer particles, which in their turn undergo the same 
change, until the whole volume has completely circulated, and 
attained a temperature of 39*2° Fah. The particles now, instead 
of becoming denser, actually expand, and so remain at the top 
until a thin layer of ice is formed. This is exactly what takes 
place in our lakes and ponds during every frost; the circulation 
continues until the whole mass attains the temperature of 39*2° 
Fah., when it is gradually and finally arrested; a thin layer of 
ice is then formed at the top, acting as a cloak to the interior, 
which, remaining always at 39*2° Fah., preserves the animals and 
fishes from the action of intense cold. 

Were it not for this fact, our lakes and rivers would all be 
frozen at the bottom, and, as water is a bad conductor of heat, 
they would in time be converted into a solid block of ice, which 
would defy the hottest rays of a tropical sun to melt. Thus we 
see that such a wise provision of Nature depends entirely on an 
apparent exception to a universal law, which is so slight that it 
requires the most delicate experiments to detect it. The freezing 
point of a liquid is almost invariably the same as its melting 
point; that is, if we cool a liquid below its melting point, it will 
become solid. There are, of course, many exceptions to this, and 
even water has been known to be cooled down to 4° Fah. without 
freezing. To effect this, however, water most be kept perfectly 


THE ENGINEER’S HANDY-BOOK. 


517 


still, as, with the least vibration, congelation commences, and the 
temperature will instantly rise to zero. 

When a substance solidifies or freezes, there is always a change 
of volume, which usually is a contraction ; but, in the case of water, 
an expansion takes place. The expansion of water at the freezing 
point is by no means gradual, but takes place almost instantane¬ 
ously, and the amount of force exerted at the time is enormous. 
It has been demonstrated by actual experiments, that in freezing, 
water exerts a pressure of about 30,000 lbs. per square inch, which 
far surpasses the strain that any of our machinery could bear. 

Pure water is composed of hydrogen and oxygen in the pro¬ 
portions of two measures of hydrogen to one of oxygen, or one 
part of hydrogen to 8 of oxygen; or oxygen, 89 parts by weight, 
and by measure 1 part; hydrogen, by weight, 11 parts, and by 
measure, 2 parts; but pure water is not attainable, nor is it to be 
found in the laboratory of the chemist. Fortunately, however, 
pure water is not necessary, nor even desirable, for either house¬ 
hold or manufacturing purposes; because the presence of air and 
other gases adds very materially to the ease with which steam 
may be generated, while the ammonia, which most water contains, 
improves it for manufacturing purposes. 

The specific gravity of all waters is not the same. Sea water 
varies from T0269 to 1*0285, the mean being 1*0277, thus requir¬ 
ing 34*9741 cubic feet of sea water to make one ton, and about 
35 feet of fresh water. Water is heavier at night than during the 
day, owing to the atmosphere being more dense, and the additional 
weight of the dew. 

Water has the greatest specific heat of all known liquids ex¬ 
cept hydrogen, and is therefore taken as the standard for all solids 
and fluids. The latent heat of water is 143° Fall., and that of 
ice 140°, as it absorbs that amount of heat in changing from a 
liquid to a solid state. 

Water, under the influence of heat, can be changed from the 
liquid to the gaseous state in two ways only, either by conversion 
into steam, or by decomposition into its constituent gases, hydrogen 
44 


518 


THE ENGINEER'S HANDY-BOOK. 


and oxygen, which decomposition can be effected only at the ex 
pense of the apparatus in which it is effected. 


TABLE 

SHOWING THE QUANTITY AND WEIGHT OF WATER IN PIPES ONE FATHOM 
IN LENGTH (6 FEET), AND OF DIFFERENT DIAMETERS FROM 1 TO 12 
INCHES. 


Diameter 
in Inches. 

Quantity in 
Cubic Inches. 

Quantity in Im¬ 
perial Gallons. 

Weight in Lbs. 
Avoirdupois. 

* 

14*14 

0-051 

0-51 

1 

56-55 

0-205 

2*05 

u 

127-23 

0-460 

4-60 

2 

226-19 

0-818 

8-18 

2* 

353-43 

1-278 

12-78 

3 

508-94 

1-841 

18-41 

3* 

692-72 

2-506 

25-06 

4 

904-78 

3-272 

32-72 

41 

1145-11 

4-142 

41-42 

5 

1413-72 

5113 

51-13 

51 

1710-60 

6-187 

61-87 

6 

2035-75 

7-363 

73-63 

61 

2389-18 

8-641 

86*41 

7 

2770-88 

10-022 

100-22 

71 

3180-86 

11-505 

11505 

8 

361911 

13-090 

130-90 

81 

4085-64 

14-777 

147*77 

9 

4580-44 

16-567 

165-67 

91 

5103-52 

18-459 

184-59 

10 

5654-87 

20-453 

204-53 

101 

6234-49 

22-550 

225-50 

11 

6842-39 

24-748 

247-48 

111 

7478-56 

27-049 

270-49 

12 

8143-01 

29-452 

294-52 

121 

8835-74 

38-32 

319-50 

13 

9556-74 

55-3 

34500 

131 

1030601 

59-6 

373-50 

14 

11083-56 

65-2 

400-50 





















519 


THE ENGINEER’S HANDY-BOOK. 


TABLE 


SHOWING THE QUANTITY OF WATER PER LINEAL FOOT IN PUMPS, OR 
VERTICAL PIPES OF DIFFERENT DIAMETERS. 


Diameter 
of Pump 
in Inches. 

Number of 
Gallons 
per Lineal 
Foot. 

Number of 
Cubic Feet 
per Lineal 
Foot. 

Diameter 
of Pump 
in Inches. 

Number of 
Gallons 
per Lineal 
Foot. 

Number of 
Cubic Feet 
per Lineal 
Foot. 

2 

•136 

•0218 

8 

2176 

•3490 

21 

•172 

•0276 

81 

2-314 

*3712 

21 

*212 

•0340 

81 

2-456 

•3940 

21 

•257 

•0412 

81 

2-603 

•4175 

3 

*306 

•0490 

9 

2-754 

•4417 

31 

•359 

•0576 

91 

2-909 

•4666 

31 

•416 

•0668 

91 

3-068 

•4923 

31 

*478 

•0766 

91 

3-232 

•5184 

4 

*544 

•0872 

10 

3-400 

•5454 

41 

•614 

•0985 

101 

3-572 

•5730 

41 

•688 

•1104 

101 

3-748 

•6013 

41 

•767 

•1230 

101 

3-929 

•6302 

5 

•850 

*1363 

11 

4114 

•6599 

51 

•937 

•1503 

111 

4-303 

•6902 

51 

1-028 

•1649 

111 

4-496 

•7212 

51 

1-124 

•1803 

111 

4-694 

•7529 

6 

1-224 

•1963 

12 

4-896 

•7853 

61 

1-328 

•2130 

121 

5-312 

•8521 

61 

1-436 

•2304 

13 

5-746 

•9217 

61 

1-549 

•2489 

131 

6*196 

•9939 

7 

1-666 

•2672 

14 

6*664 

1-0689 

71 

1-787 

•2866 

15 

7*650 

1-2271 

71 

1*912 

•3067 

16 

8-704 

1-3962 

71 

2-042 

•3275 

18 

11016 

1-7670 


One cubic foot of water weighs 621 lbs., and contains 71 U. S. 
gallons. 

One cubic foot of ice weighs 57 lbs. 
















520 


THE ENGINEER’S HANDY-BOOK 


TABLE 

SHOWING THE WEIGHT OF WATER AT DIFFERENT TEMPERATURES. 


Temperature, 

Bail 

W EIGHT OF A 

Cubic Foot 
in Lbs. 

Temperature, 

Fah. 

Weight of a 
Cubic Foot 
in Lbs. 

40° 

62*408 

172° 

60-72 

42° 

62-406 

182° 

60-55 

52° 

62-377 

192° 

60-28 

62° 

62-321 

202° 

60-05 

72° 

62-025 

212° 

59-82 

82° 

62-015 

230° 

59-37 

92° 

62-004 

250° 

58-85 

102° 

61-092 

275° 

58-17 

112° 

61*078 

300° 

57-42 

122° 

61-063 

350° 

55-94 

132° 

61-047 

400° 

54-34 

142° 

61-030 

450° 

52-70 

152° 

61-011 

500° 

51-02 

162° 

60-092 

600° 

47-64 


TABLE 

SHOWING THE BOIEING POINT FOR FRESH AVATER AT DIFFERENT ALTI¬ 
TUDES ABOVE SEA-LEVEL. 


Boiling Point 
in Deg. Fah. 

Altitude 
above Sea- 
Level in Feet. 

Boiling Point 
in Deg. Fah. 

i i ■ 

Altitude 
above Sea- 
Level in Feet 

Boiling Point 
in Deg. Fah. 

Altitude 
above Sea- 
Level in Feet. 

184° 

15,221 

195° 

9,031 

206° 

3,115 

185 

14,649 

196 

8,481 

207 

2,589 

186 

14,075 

197 

7,932 

208 

2,063 

187 

13,498 

198 

7,381 

209 

1,539 

188 

12,934 

199 

6,843 

210 

1,025 

189 

12,367 

200 • 

6,304 

211 

512 

190 

11,799 

201 

5.764 

212 

Sea-Level = 0 

191 

11,243 

202 

5,225 



192 

10,685 

203 

4,697 

BeloAv Sea-Level 

193 

10,127 

204 . 

4,169 

213 

511 

194 

9,579 

205 

3,642 



















































TABLE 

SHOWING THE CAPACITY OF CISTERNS AND TANKS. COMPUTED IN BARRELS OF 31 £ GALLONS. 


521 


THE ENGINEER’S HANDY-BOOK. 



Oo 

373*0 

© 

b 

H 

H 

Ol 

Ol 

Ol 

40 

X 

. 

ZD 

05 

1C 

1 671*4 

© 

b 

h 

r- 

© 

b 

Ol 

X 

Ol 

*b 

© 

X 

8-696 

1044*4 

1119*0 

1193*6 

Ol 

do 

© 

Ol 
1—1 

X 

Ol 

X 

rH 

1417*4 

© 

Ol 

© 

^H 

C* 

CO 

© 

CO 

CO 

b 

o 

co 

• 

rH 

i- 

H 

ZD 

do 

X 

lO 

05 

»b 

o 

CO 

X 

X 

i- 

CO 

© 

b 

-r 

i- 

05 

b 

© 

X 

Ol 

»b 

L- 

X 

© 

01 

rr 

© 

© 

05 

© 

Ol 

b 

I- 

© 

ri 

© 

b 

r-^ 

o> 

rH 

rH 

Ol 

Ol 

05 

l" 

Ol 

rH 

© 

© 

H 

X 

rH 

Q£ 

rH 

rH 

01 

o 

co 

co 

Ol 

© 

x 

o 

co 

Ol 

h 

H 

•co 

X 

H 

X 

CO 

H 

IO 

X 

b 

© 

ZD 

l- 

b 

© 

© 

rH 

b 

01 

in 

© 

»b 

X 

in 

© 

© 

X 

© 

© 

© 

00 

© 

© 

© 

Ol 

b 

Ol 

© 

rH 

1- 

b 

9S 

r 

00 

'H 4 

rH 

rH 

© 

do 

o 

Ol 

h* 

rH 

>o 

05 

© 

Ol 

H 

CO 

Ol 

CO 

CO 

b 

1- 

X 

Ol 

T-H 

X 

h 

rH 

8 

© 

b 

C0 

iO 

© 

di 

© 

LO 

X 

b 

-r 

© 

L— 

b 

o 

i- 

© 

b 

LO 

l- 

© 

do 

© 

X 

-■f 1 

Ol 

© 

X 

X 

© 

rH 

© 

Ol 

© 

i- 

© 

1—H 

b 

Ol 

© 

rH 

© 

GO 

I- 

© 

H 

rH 

I- 

00 

CO 

Ol 

© 

s 

Ol 

Ol 

b 

X 

X 

o 

Ol 

X 

X 

t- 

b 

Ol 

Tin 

H 

b 

H 

Ol 

© 

Ol 

© 

© 

di 

r- 

IO 

in 

© 

01 

© 

-r 

do 

© 

© 

Ol 

© 

rH 

05 

CO 

© 

1- 

© 

r^ 

X 

H 

05 

LO 

X 

rH 

b 

© 

© 

b 

© 

© 


00 

05 

o 

0.1 

GO 

rH 

LO 

Ol 

L- 

CO 

05 

Ol 

I- 

>b 

X 

X 

t~ 

b 

l- 

X 

CO 

05 

h 

• dP 

T-H 

© 

IO 

X 

© 

IO 

© 

«b 

§< 

© 

© 

b 

X 

© 

© 

Ol 

© 

t-h 
l - 

© 

'O 

X 

rH 

X 

© 

© 

1- 

X 

b 

© 

X 

05 

X 

X 



oo 

X 

05 


o 

‘O 

rH 

© 

Ol 

X 

X 

© 


© 

© 

rH 


H 

di 

05 

ib 

bi 

05 

LO 

01 

do 

© 


do 

b 


do 

rfH 



hH 

OO 

rH 

lO 

© 

Ol 

co 

© 

X 


T-H 

*—b 

X 

Ol 

© 

© 

X 

H 


1—1 

Ol 

Ol 

Ol 

X 

X 

-r 

-t* 

-t- 

© 

© 

© 

© 

CO 

© 

i- 

W 


CO 

rH 

co 

rH 

l~ 

Ol 

i- 

Ol 

i- 

co 

X 

X 

X 

X 

© 



«© 

1- 


© 

Ol 

X 

*b 

© 

GO 

05 

rH 

Ol 

b 

lb 

b 

GO 

© 

Y 

rH 

*0 

X 


© 

X 

rH 

, -r 

1" 


-t 

1- 


X 

© 

© 

X 



rH 

rH 

Ol 

Ol 

Ol 

X 

co 

X 

-t 1 

'-f 4 

-f 

© 

© 

© 

© 

© 

« 

K 


CO 

rH 

o 

X 

1- 

co 

-r 

X 

rH 

© 

X 

1- 

© 

-r 

X 

rH 

H 

w 

b 

rH 

00 

b 

rH 

do 

LO 

01 

05 


Ol 

Cg 1 

© 

co 

© 



r* 

CO 

CO 

X 

rH 

-t 

© 

© 

Ol 


r~ 

© 

Ol 

LO 

X 

rH 

X 



rH 

rH 

rH 

Ol 

01 


Ol 

X 

X 

X 


—t 4 

b 

H 

© 

© 

« 


X 

H 

o 

LO 

rH 


Ol 

X 

-r 

© 

© 

^H 

© 

Ol 

X 

X 

. 


Cl 

© 

do 

b 

X 

*b 

do 

© 

CO 

© 

do 

rH 

X 

© 

do 

rH 


rH 

rH 

X 

lO 

X 

o 

Ol 

-t 

1- 

© 

rH 

X 

© 

X 

© 

Ol 

© 



rH 

rH 

r— - 

rH 

Ol 

Ol 

Ol 

01 

01 

X 

X- 

X 

X 


H 

Tt- 



OI 

05 

CO 

Ol 

05 

IO 

rH 

X 


rH 

X 

-r 

© 


X 

© 


o 

C0 

rH 

o 

05 

b 

b 

b 

X 

Ol 

rH 

05 

do 

b 

© 

b 

X 


rH 

05 

rH 

CO 

-f 

CO 

X 

© 

Ol 

-H 

© 

l- 

© 

rH 

X 

© 

N 




rH 

rH 

rH 

rH 

rH 

Ol 

Ol 

01 

Ol 

Ol 

Ol 

X 

co 

X 

X 



© 

CO 


05 

© 

rH 

Ol 

X 


© 

© 

t- 

X 

© 

© 

rH 


05 

© 

© 

>b 

b 

b 

rH 

b 

rH 

© 

rn 

b 

H 

© 

Ol 

b 

Ol 



l- 

05 

o 

Ol 

X 

LO 

© 

X 

© 

rH 

01 

-t- 

© 

t~ 

X 

© 





rH 

rH 

rH 

rH 

rH 

rr 

H 

Ol 

01 

Ol 

Ol 

01 

Ol 

cc 



I' 

I' 

CO 

iO 

-r 

-r 

X 

Ol 

Ol 

rn 

© 

© 

© 

X 

X 

(H 


X 

05 

rH 

X 

LO 

i' 

© 

rH 

X 

© 

i- 

© 

rH 

Ol 

H 

© 

do 



>o 

i- 

X 

05 

© 

rH 

X 


© 

© 

l- 

© 

© 

rH 

01 

X 







rH 

rH 

rH 

rn 

rH 

rH 

rH 

rH 

Ol 

Ol 

Cl 

Ol 




X 

o 

rH 

01 

H 

© 

i- 

X 

© 

rH 

Ol 


© 

© 

X 


i- 

LO 

b 

h 

X 

01 

rH 

b 

© 

do 

Ih 

b 

© 

© 


X 

Ol 



-v 

LO 

CO 

t- 

X 

© 

© 

© 

rH 

01 

X 


© 

© 

1- 

X 









rH 

rH 

rH 


rH 

rH 

rH 

t-h 

rH 

r 



CO 

X 

o 

t- 

h 

rH 

© 

© 

X 

© 

in 

Tf 

rH 

© 

© 

X 


© 

CO 

o 

b 

X 

© 

N 

X 

© 

b 

b 


r- 

b 

© 

b 

b 



X 



IO 

co 

co 

i- 

X 

X 

© 

© 

© 

rH 

Ol 

OI 

X 













rH 

rH 

t-h 

rH 

rH 

rH 



X 

o 

t- 

X 

© 

In 

X 

© 

1- 

X 

© 

i- 

X 

© 

i- 

X 



CO 

X 

(01 

I- 

Ol 

b 

rH 

b 

© 

© 

© 

b 

© 


X 

CC 



Ol 

01 

X 

X 

H 


iO 

© 

© 

© 

1- 


i- 

X 

X 

© 



© 


h. 

X 

a 

© 

rH 

01 

0? 


© 

© 

It. 

oo 

© 

© 

HXdag 






t-h 

rH 

rH 

rH 

rH 

hH 

rH 

t-h 

t-H 


Ol 


44 * 

































































522 


THE engineer’s HANDY-BOOK. 



0) 

73 

o 

fa 

m 


c3 « 

a> 

o 

a 


S_ -t-> 

a 


a 


c 




H 

£ a 




a 

. ^ 




w 

fa 

^ fa 

• d» 

CO 

13 

or 

•H 

<x> 

O 

a ft 

o 


a 

O 

o 

CO 




H 

a 

k 

< 


a 

5 

o 

H 

X 

a 

H 

-< 

* 

W 

to 

w 

•< 

« 

C 

H 

Q 

K 

« 

M 

X 

O' 

K 

W 

« 

a 

£ 

o 

a 

a 

s 

H 

O 

►X 

£ 

o 

x 

CO 


cT 

<M 

o 

.22 

o5 

3 

Feet 

t- 

GO 

rH 

d 

© 


to 

© 


cc 

© 

© 

© 

© 

© 

© 

© 

© 

© 

© 

rn 

o 

H 


O 

a 






Hi 

d 

© 

Tf 

to 

© 

i- 

cc 

© 

H 

O 

•H 

& 

a 

•H 




g 

8 

© 

to 

© 

© 

© 



© 

to 

S3 

1- 

© 

rH 

© 

cc 

if 

to 

o 

PlJ 




-4© 

S3 

i- 

© 

rH 

© 

<X) 


to 

i- 

© 

no 

© 

to 

rH 

© 

r- 

fa 

a 

o 


tx 

o 

(D 

0) 

tq 

i— 

CO 

to 

© 

to 

rH 

© 

I- 

cc 

to 

~f 

CO 

d 

d 

d 

rH 

rH 

*"* 

s< 

O 


ft 

i- 

® r 

to 

fa 

CO 

d 

d 

d 

rH 

rH 










s 






l-H 



















o 

© 
























« 

m 

o 

3 

Feet 

Jx 

Gals 

rH 

d 

© 

Tf 

to 

© 

t- 

cc 

© 

© 

© 

© 

© 

© 

© 

© 

© 

© 

© 

© 












H 

d 

© 

->f 

to 

© 

I- 

00 

© 

© 

fc 

rfa 

0 























fi 


s 





© 

© 

© 

© 

© 

<d 

to 

© 

© 

© 


to 

© 

8 

Tf 

h- 

© 

8 

fa 

Ol," 






© 

© 

to 

© 

© 

If 


© 

© 

to 


t' 

© 

rH 

CC 

© 

*< 

>• 


a? 

«—< 
3 

o 

0) 

© 

to 

#1 

© 

I- 

© 

CN 

to 


Q0_ 

©_ 

to 

I- 

to 

© 

© 

d 

d 

th 

rH 

rn 


a 

3s 

a 


ft 

to 


to 

© 

© 

d 

d 

rn 

rH 

rH 










to 

a 

a 

& 

H 

M 

co 





rH 



















a> 

t/i 

•^4 

c$ 

u 

a5 

3 

Feet 

lx 

o 

Gals. 

rH 

d 

© 


to 

© 

t~ 

cc 

© 

o 

rH 

20 

30 

8 

50 

09 

70 

8 

90 

© 

© 

n 

fa 


c 























■< 

> 

a 




© 

8 

© 

to 

© 

© 

to 

d 

cc 

© 

to 

© 

d 

© 

cc 

cc 

© 

00 

to 

H 

ft 




-fa 

© 

© 

d 

© 

uo 

OO 

© 

cc 

to 

Ol 

rH 

H 

to 

© 

t- 

to 

© 

Ol 



o 


c 


to 

d 

rH 


to 

© 

JD- r 

tq 

CO 

Ol 

© 

if 

© 

d 

d 

rH 

rH 

rH 

rn 

fa 

fa 

a 

3. 

a 


fan 

d r 

© r 

fa 

© r 

of 

d r 

H 

H 

11 

rH 











d©if» 0 ©l>CC©©®©© 

ri (M CO ^ 


O O 

co r- 


o o 
co o 


o 

o 

o 


CO 

co 

CO 


o 

© 

© 


O CO N 


© 

© 


d 

d 


© 

d 


CO to _ . 

CO X *0 (N © 

r> • - C' #■- c ^ ^ 

CEO^CONO^NOlrt 


© 

© 

© 


© 

© 

© 


© 

© 

Tt< 


© tO © d © 

© 00 lO CM © 

CO d <M d CM 


a> 

to 

'3 ® 

,2 3 

“ £3 

*3 

0, u 

_• o 

W ft 
-1 


<D 

Sx 

73 

0) 

O 

*3 



O 

73 


-fa 


Sx 


13 

o 

*<x> 

O 


£ 


OHNCO'tIO©!' 


oo©©©©©©©©©©© 

nd©iftO©l^aO©© 


© 

© 

© 


© 

© 

© 


CO 

© 


© 

© 


© 

© 

© 


CO lO 

no co of d 


© oo © 

CO Ol lO 
- If 


© 


Ol 


© © © © © 

© © © to © 

© lO © (M Cl 


© CM lO 
© if d 


05 

'3 <D 

,2 3 
— c 

* £ 

ft a 

• o» 

a ft 

eo 


a: t- i 2 
« © OS 

ft o 


i—i d © if to © 


00 ©©©©©©©© 


d © 


© I- 


. © © 

2, u v © *0 

cs O 4 > to l— 

^ ^ t-f CO (M 


8 tOOOONMOtO©NOiON 
NOtOl^MMtONtOQOtaCIO 
tOXtOOlOOJXNMClHHHrt 


© 

© 


© © 
© © 


© to 

© A- 




a> 

in 

*3 aJ 

a .3 

* a 

^ £ 
a 


•X »5 

OJ u T 3 
CD o £ 

ft C 


d©iftO©A- 00 ©©©©©©©©©© 

H 01 ©rtiO®l'XO 


• 00 ©©©«Tt-tOiOO©® 

^tHV©©©to©00i-iOlto©to© 

«0®OiO©(MOXb-©iOiOlNH 

rK f y , r- rv r> r 

^ ” to 0-1 t-H 1—>( 1-1 


© © rH d lO 

© 00 A- © to 


A <D 
0 ) i n 
cn 

«- a 
O u 

a a 

• H 

- * 


■g £ 

•« (2 


3 
3 

« 3 


u 

<v 

o. 


© 

© 

ft 


J 2 

Is 

O 


i-id©ifto©txao© 


©©©©©©© 
r-l Ol © if to © A- 


© © 
© © 


.OOMtOO©N(MNQ«5 
a ^OiOWOlOHtOHhiOlM 
cSo©tOdOO®iOif©©ddii 
S of r-f 


d 

© 


h lO h b- lO 

if © © d d 



























THE ENGINEER’S HANDY-BOOK. 


523 


TABLE 

SHOWING THE CAPACITY OF CISTERNS IN GALLONS FOR EACH 10-INCH 

DEPTH. 


Diameter 
in Feet. 

Gallons. 

Diameter 
in Feet. 

Gallons. 

Diameter 
in Feet. 

Gallons. 

2* 

19-5 

6*5 

2068 

12 

705* 

2*5 

30*5 

7* 

239-8 

13 

827-4 

3* 

44*6 

7*5 

275-4 

14 

959-7 

3-5 

59*97 

8* 

313-3 

15 

1101-6 

4* 

78*33 

8*5 

353*7 

20 

1958-4 

45 

99*14 

9* 

396-5 

25 

3059-9 

5* 

122*4 

9*5 

461-4 

30 

4406-4 

5*5 

148*1 

10* 

489-6 

35 

5990- 

6* 

176-2 

11* 

592-4 

40 

7831- 


Rule for finding the horse-power of waterfalls. — Multiply the 
area of the cross-section of the waterfall in feet by its velocity in 
feet per minute; this product will give the number of cubic feet 
flowing through per minute. Multiply this by 62^ lbs., the number 
of pounds in a cubic foot of water. Multiply this last product by 
the fall in feet, and divide by 33,000. The quotient will be the 
horse-power of the waterfall. 

Example. —With a stream or flume 10 feet; depth, 4 feet; area 
of cross-section, 40 feet; velocity in feet per minute, 150. Then 
40 X 150 = 6,000 cubic feet of water per minute; 6,000 x 621 — 
375,000 pounds of water per minute. 10 x 375,000 = 3,750,000 
foot-pounds of the waterfall; 3,750,000 -r- 33,000 = 113y 7 T horse¬ 
power of the waterfall. 

Rule for finding the contents of an elliptic or oval tank in cubic 
feet or gallons. —Multiply the long diameter in inches by the 
short diameter in inches, this product by *7854, and this last product 
by the height of the tank in inches; then divide by 1728, and the 
result will be the contents of the tank in cubic feet, which, if mul¬ 
tiplied by 7*5, gives the number of U. S. gallons in the tank. 

















524 


THE ENGINEER’S HANDY-BOOK. 

Rule for finding the quantity of water which any square or rectan¬ 
gular box, or tank , is capable of containing in cubic feet or U. S. 
gallons. — Multiply the length of the sides in inches by their height 
in inches; then multiply the width of the ends in inches by their 
height in inches. Add these two products together and divide by 
1728; the product will be the contents in cubic feet. This re¬ 
sult being multiplied by 7'5 gives the cubical contents in U. S. 
gallons. 

Rule for finding the cubical contents of a triangular tank. — Mul¬ 
tiply the length of the base by half its height; multiply this by 
.7854, then divide the product by 1728; the quotient will be the 
number of cubic feet, which, if multiplied by 7‘5, will give the 
number of U. S. gallons in the tank. 

TABLE 


SHOWING THE DAILY AVERAGE NUMBER OF GALLONS OF WATER PER 
INDIVIDUAL IN DIFFERENT CITIES INCLUDING THE QUANTITY USED 
FOR MANUFACTURING PURPOSES, FOUNTAINS, ETC. 


Washington, D. C. . 

. . 158 

Toronto . 

. 77 

New York .... 

. . 100 

London, England. . . 

. 29 

Brooklyn. 

. . 50 

Liverpool, “ . . . 

. 23^ 

Philadelphia . . . 

. . 55 

Glasgow, Scotland . . 

. 50 

Baltimore .... 

. . 40 

Edinburgh, “ . . 

. 38 

Chicago. 

. . 75 

Dublin, Ireland . . . 

. 25 

Boston. 

. . 60 

Paris, France . . . 

. 28 

Albany, N. Y.. . . 

. . 80 

Tours, “ ... 

. 22 

Detroit. 

. . 83 

Toulouse, “ ... 

. 26 

Jersey City, N. J. . 

. . 99 

i Lyons, “ ... 

. 20 

Buffalo, N. Y. . . . 

. . 61 

: Leghorn, Italy. . . . 

. 30 

Cleveland .... 

. . 40 

Berlin, Prussia . . . 

. 20 

Columbus .... 

. . 30 

Hamburg, “ ... 

. 33 

Montreal .... 

. . 55 

Richmond, Va. . . . 

. 36 

San Francisco . . 

. . 42 

City of Mexico . . . 

. 25 

Hartford, Conn. . . 

. . 32 

Vienna. 

. 20 

Charleston, S. C. . . 

. . 27 

St. Petersburg . . . 

. 19 

















525 


THE ENGINEER’S IIANDY-BOOK. 

Tapors. 

The mechanical properties of vapor are similar to those of 
gases in general. When a vapor or gas is contained in a close 
vessel, the inner surface of the vessel will sustain a pressure arising 
from the elasticity of the fluid. This pressure is produced by the 
mutual repulsion of the particles, which gives them a tendency to 
fly asunder, and causes the mass of the fluid to exert a force tend¬ 
ing to burst any vessel within which it is confined. This pressure 
is uniformly diffused over every part of the surface of the vessel 
in which such fluid is contained. It is to this quality that all the 
mechanical power of steam is due. 

It is well known from common observation, that liquids, if not 
confined in close vessels, become transformed into a condition re¬ 
sembling gases at ordinary temperatures, and then disappear. 
This transformation takes place in nearly all liquids more or less 
rapidly at ordinary temperatures, though in some it takes place 
at a very low temperature and at an imperceptible rate of evap¬ 
oration ; the lighter the specific gravity, the more rapidly it will 
disappear. 


TABLE 

SHOWING THE TEMPERATURE OF SATURATED VAPOR IN ATMOSPHERES, 

ACCORDING TO ZEUNER. 


Atmospheres. 

Temperature in 
Degrees Fah., 
Water. 

Atmospheres. 

Temperature in 
Degrees Fah., 
Water. 

1 

212° 

6 

318-5° 

2 

248° 

7 

329-5° 

3 

to 

to 

o 

8 

3390° 

4 

291° 

9 

3480° 

5 

306° 

10 

357-0° 











526 


THE ENGINEER’S HANDY-BOOK. 

TABLE 


SHOWING THE PRESSURE AND TEMPERATURE OF THE VAPORS OF WATER 

FROM 32° TO 400° FAH. 


Temp. 

Fah. 

Pressures 
in Atmos¬ 
pheres. 

Pressures 
in Lbs. per 
Sq. Inch. 

Differ¬ 

ences. 

Temp. 

Fah. 

Pressures 
in Atmos¬ 
pheres. 

Pressures 
in Lbs. per 
Sq. Inch. 

Differ¬ 

ences. 

32 

0-006 

0-09 

o-oo 

73 

0*026 

0-38 

0-02 

33 

0-006 

0-09 

000 

74 

0*027 

0-40 

o-oi 

34 

0-006 

0-09 

o-oi 

75 

0-028 

0*41 

0-02 

35 

0-007 

o-io 

0*00 

76 

0*029 

0-43 

0 03 

36 

0-007 

o-io 

o-oi 

77 

0-031 

0*46 

o-oo 

37 

0-007 

0-11 

0*01 

78 

0-031 

0*46 

o-oi 

38 

0-008 

0-12 

o-oo 

79 

0-032 

0*47 

o-oo 

39 

0-008 

0-12 

0*01 

80 

0-032 

0-47 

0-02 

40 

0*009 

0-13 

o-oo 

81 

0*033 

0-49 

o-oi 

41 

0*009 

0-13 

o-oi 

82 

0034 

0*50 

0-03 

42 

0-009 

0*14 

o-oo 

83 

0-036 

0-53 

o-oi 

43 

0-009 

0-14 

o-oi 

84 

0-037 

0*54 

0*03 

44 

o-oio 

0-15 

0-00 

85 

0-039 

0*57 

0-03 

45 

o-oio 

0*15 

0*01 

86 

0*041 

0-60 

0*02 

46 

o-on 

0-16 

o-oo 

87 

0-042 

0*62 

o-oi 

47 

o-oii 

0-16 

o-oi 

88 

0-043 

0-63 

0*02 

48 

o-on 

0-17 

0-00 

89 

0-044 

0-65 

0-03 

49 

o-on 

0-17 

o-oi 

90 

0*046 

0-68 

003 

50 

0-012 

0-18 

o-oo 

91 

0-048 

0*71 

o-oi 

51 

0-012 

0-18 

0*01 

92 

0-049 

0*72 

0-02 

52 

0-013 

0-19 

0*01 

93 

0-050 

0-74 

0-02 

53 

0*013 

0-20 

0*01 

94 

0-052 

0*76 

0*05 

54 

0-014 

0-21 

o-oo 

95 

0-055 

0-81 

0*03 

55 

0014 

0-21 

0-01 

96 

0-057 

0-84 

o-oi 

56 

0-015 

0-22 

0-02 

97 

0*058 

0*85 

0-05 

57 

0-016 

0-24 

0-00 

98 

0-061 

0-90 

0*00 

58 

0-016 

0-24 

o-oi 

99 

0-061 

0-90 

0*03 

59 

0-017 

0-25 

o-oi 

100 

0-063 

0-93 

0-04 

60 

0-018 

0-26 

0-00 

101 

0*066 

0-97 

0*01 

61 

0-018 

0-26 

o-oo 

102 

0*067 

0-98 

0*03 

62 

0-018 

0-26 

0-02 

103 

0*069 

1*01 

0*05 

63 

0-019 

0*28 

0-01 

104 

0-072 

1-06 

0-03 

64 

0-020 

0-29 

0-00 

105 

0-074 

1-09 

0-06 

65 

0-020 

0-29 

0-02 

106 

0-078 

1*15 

o-oi 

66 

0'021 

0-31 

o-oi 

107 

0-079 

1*16 

0*02 

67 

0-022 

0-32 

0-02 

108 

0-080 

1*18 

0-04 

68 

0-023 

0-34 

o-oo 

119 

0*083 

1*22 

0-04 

69 

0-023 

0-34 

o-oi 

110 

0*086 

1-26 

0-03 

70 

0-024 

0*35 

0*00 

111 

0-088 

1-29 

0-05 

71 

0-024 

0*35 

0-02 

112 

0-091 

1*34 

0*03 

72 

0-025 

0-37 

o-oi 

113 

0-093 

1*37 

0-03 



























527 


THE ENGINEER’S HANDY-BOOK. 


TABLE — ( Continued.) 


Temp. 

Fah . 

Pressures 
in Atmos¬ 
pheres. 

Pressures 
in Lbs. per 
Sq. Inch. 

Differ¬ 

ences. 

Temp. 

Fah. 

Pressures 
in Atmos¬ 
pheres. 

Pressures 
in Lbs. per 
Sq. Inch. 

Differ¬ 

ences. 

114 

0*095 

1*40 

0*07 

157 

0*300 

4*41 

0*09 

115 

0*100 

1*47 

0*03 

158 

0*306 

4*50 

0*03 

116 

0*102 

1*50 

0*04 

159 

0*308 

4*53 

0*14 

117 

0*105 

1*54 

0*03 

160 

0*318 

4*67 

0*11 

118 

0*107 

1*57 

0*08 

161 

0*325 

4*78 

0*19 

119 

0*112 

1*65 

0*03 

162 

0*338 

4*97 

0*10 

120 

0*114 

1*68 

0*04 

163 

0*345 

5*07 

0*12 

121 

0*117 

1*72 

0*06 

164 

0*353 

5*19 

0*12 

122 

0*121 

1*78 

0*04 

165 

0*361 

5*31 

0*14 

123 

0*124 

1*82 

0*05 

166 

0*371 

5*45 

0*12 

124 

0*127 

1*87 

0*04 

167 

0*379 

5*57 

0*02 

125 

0*130 

1-91 

0*09 

168 

0*387 

5*69 

0*13 

126 

0*136 

2*00 

0*04 

169 

0*396 

5*82 

0*13 

127 

0*139 

2*04 

0*05 

170 

0*405 

5*95 

0*15 

128 

0*142 

2*09 

0*06 

171 

0*415 

6*10 

0*15 

129 

0*146 

2*15 

0*05 

172 

0*425 

6*25 

0*16 

130 

0*150 

2*20 

0*06 

173 

0*436 

6*41 

0-13 

131 

0*154 

2*26 

0*06 

174 

0*445 

6*54 

0*15 

132 

0*158 

2*32 

0*06 

175 

0*455 

6*69 

0*16 

133 

0*162 

2*38 

0*06 

176 

0*466 

6*85 

0*15 

134 

0*166 

2*44 

0*09 

177 

0*476 

7*00 

0*15 

135 

0*172 

2*53 

0*04 

178 

0*488 

7*15 

0*21 

136 

0*175 

2*57 

0*09 

179 

0*501 

7*36 

0*18 

137 

0*181 

2*66 

0*03 

180 

0*513 

7*54 

0*12 

138 

0*183 

2*69 

0*12 

181 

0*521 

7*66 

0*15 

139 

0*191 

2*81 

0*07 

182 

0*531 

7*81 

0*17 

140 

0*196 

2*88 

0*06 

183 

0*543 

7*98 

0*19 

141 

0*200 

2*94 

0*07 

184 

0*556 

8*17 

0*19 

142 

0*205 

3*01 

008 

185 

0*569 

8*36 

0*18 

143 

0*210 

3*09 

0*10 

186 

0*581 

8*54 

0*18 

144 

0*217 

3*19 

0*04 

187 

0*593 

8*72 

0*17 

145 

0*220 

3*23 

0*09 

188 

0*605 

8*89 

0*19 

146 

0*226 

3*32 

0*08 

189 

0*618 

9*08 

0*21 

147 

0*231 

3*40 

0*10 

190 

0*631 

9*29 

0*21 

148 

0*238 

3*50 

0*10 

191 

0*646 

9*50 

0*22 

149 

0*245 

3*60 

0*09 

192 

0*661 

9*72 

0*22 

150 

0*251 

3*69 

0*02 

193 

0*676 

9*94 

0*22 

151 

0*259 

3*81 

0*09 

194 

0*691 

10*16 

0*20 

152 

0*265 

3*90 

0*08 

195 

0*705 

10*36 

0*21 

153 

0*271 

3*98 

0*11 

196 

0*719 

10*57 

0*22 

154 

0*278 

4*09 

0*10 

197 

0*734 

10*79 

0*22 

155 

0*285 

4*19 

0*06 

198 

0*749 

11*01 

0*22 

156 

0*289 

4*25 

0 16 

199 

0*764 

11*23 

0*22 









































528 


THE ENGINEER^ HANDY-BOOK 


TABLE — ( Continued .) 


Temp. 

Fail. 

Pressures 
in Atmos¬ 
pheres. 

Pressures 
in Lbs. per 
Sq. Inch. 

Differ¬ 

ences. 

Temp. 

Fah. 

Pressures 
in Atmos¬ 
pheres. 

Pressures 
in Lbs. per 
Sq. Inch. 

Differ¬ 

ences. 

200 

0-770 

11-45 

0-12 

243 

1-794 

26-37 

0-47 

201 

0-787 

11-57 

0-25 

244 

1-826 

26-84 

0-49 

202 

0-804 

11-82 

0-43 

245 

1-859 

27-33 

0-50 

203 

0-833 

12-25 

0-25 

246 

1-893 

27-83 

0-51 

204 

0-850 

12-50 

0-24 

247 

1-928 

28-34 

0-50 

205 

0-867 

12-74 

0-27 

248 

1-962 

28-84 

0-52 

206 

0-885 

13-01 

0*28 

249 

1-997 

29-36 

0-51 

207 

0-904 

13-29 

0-28 

250 

2-032 

29-87 

0-53 

208 

0-923 

13-57 

0-28 

251 

2-068 

30-40 

0-53 

209 

0-942 

13-85 

0-28 

252 

2-104 

30-93 

0-54 

210 

0-961 

14-13 

0-29 

253 

2 T 41 

31-47 

0-56 

211 

0-981 

14-42 

0-28 

254 

2-179 

3203 

0-57 

212 

1-000 

14-77 

0-30 

255 

2-217 

32-60 

0-56 

213 

1-020 

15-00 

0-29 

256 

2-256 

33-16 

0-56 

214 

1-040 

15-29 

0-31 

257 

2-294 

33-72 

0-59 

215 

1-061 

15-60 

0-32 

258 

2-334 

34-31 

0-59 

216 

1-083 

15-92 

0-31 

259 

2-374 

34-90 

0-60 

217 

1-104 

16-23 

0-31 

260 

2-415 

35-50 

0-60 

218 

1-125 

16-54 

0-32 

261 

2-456 

36-10 

0-62 

219 

1-147 

16-86 

0-32 

262 

2-498 

36-72 

0-63 

220 

1-169 

17 T 8 

0-33 

263 

2-541 

37-35 

0-63 

221 

1-191 

17-51 

0-35 

264 

2-584 

37-98 

0-64 

222 

1-215 

17-86 

0-34 

265 

2-627 

38-62 

0-64 

223 

1-238 

18-20 

0-34 

266 

2-671 

39-26 

0-67 

224 

1-261 

18-54 

0-35 

267 

2-716 

39-93 

0-66 

225 

1-285 

18-89 

0-35 

268 

2-761 

40-59 

0 67 

226 

1-309 

19-24 

0-37 

269 

2-807 

41-26 

0-69 

227 

1-334 

19-61 

0-37 

270 

2-854 

41-95 

0-69 

228 

1-359 

19-98 

0-38 

271 

2-901 

42-64 

0-71 

229 

1-385 

20-36 

0-44 

272 

2-949 

43-35 

0-71 

230 

1-415 

20-80 

0-40 

273 

2-997 

44-06 

0-72 

231 

1-442 

21-20 

0-39 

274 

3-046 

44-78 

0-75 

232 

1-469 

21-59 

0-42 

275 

3-097 

45-53 

0-73 

233 

1-497 

22-01 

0-41 

276 

3-147 

46-26 

0-75 

234 

1-525 

22-42 

0-41 

277 

3-198 

47-01 

0-77 

235 

1-553 

22-83 

0-43 

278 

3-250 

47-78 

0-77 

236 

1-582 

23-26 

0-44 

279 

3-303 

48-55 

0-80 

237 

1-612 

23-70 

0-42 

280 

3-357 

49-35 

0-79 

238 

1-641 

24-12 

0-43 

281 

3-411 

50-14 

0-81 

239 

1-670 

24-55 

0-44 

282 

3-466 

50-95 

0-81 

240 

1-700 

24-99 

0-45 

283 

3-521 

51-76 

0-81 

241 

1-731 

25-45 

0*45 

284 

3-576 

52-57 

0-82 

242 

1-762 

25-90 

0-47 

285 

3-632 

53-39 

0-84 



































529 


THE ENGINEER^ HANDY-BOOK. 


TABLE — ( Continued .) 


Temp . 

Fah. 

Pressures 
in Atmos¬ 
pheres. 

Pressures 
in Lbs. per 
Sq. Inch. 

Differ¬ 

ences. 

Temp. 

Fah. 

Pressures 
in Atmos¬ 
pheres. 

Pressures ’ 
in Lbs. per 
Sq. Inch. 

Differ¬ 

ences. 

286 

3-689 

54-23 

0-85 

329 

6-945 

102-09 

1-44 

287 

3-747 

55-08 

0-87 

330 

7-043 

103-53 

1*44 

288 

3-806 

55-95 

0-88 

331 

7-141 

104-97 

1-44 

289 

3-866 

56-83 

0-88 

332 

7-239 

10641 

1-46 

290 

3-926 

57-71 

0-90 

333 

7-338 

107-87 

1*45 

291 

3-987 

58-61 

0-91 

334 

7*437 

109-32 

1-46 

292 

4049 

59-52 

0-93 

335 

7-536 

110-78 

1*50 

293 

4-112 

60-45 

0-92 

336 

7-638 

112-28 

1-51 

294 

4-175 

61-37 

0-94 

337 

7-741 

113-79 

1-55 

295 

4-239 

62-31 

0-96 

338 

7-846 

115-34 

1-55 

296 

4-304 

63-27 

0-97 

339 

7-952 

116-89 

1-59 

297 

4-370 

64-24 

0-98 

340 

8-060 

118-48 

1-60 

298 

4-437 

65-22 

100 

341 

8-169 

120-08 

1-62 

299 

4*505 

66-22 

1-02 

342 

8-279 

121-70 

1-62 

300 

4"574 

67-24 

1-01 

343 

8*389 

123-32 

1-63 

301 

4-643 

68-25 

1-02 

344 

8-500 

12495 

1-65 

302 

4-712 

69-27 

1-03 

345 

8-612 

126-60 

1-64 

303 

4-782 

70-30 

1-04 

346 

8-724 

128-24 

1-68 

304 

4-853 

71-34 

1-06 

347 

8-838 

129 92 

1-69 

305 

4-925 

72-40 

107 

348 

8-953 

131-61 

1-72 

306 

4-998 

73-47 

1-09 

349 

9-070 

13333 

1-75 

307 

5-072 

74-56 

1-10 

350 

9-189 

135-08 

1-78 

308 

5147 

75-66 

1-12 

351 

9-310 

136-86 

1-81 

309 

5*223 

76-78 

1-13 

352 

9-433 

138-67 

1-80 

310 

5-300 

77-91 

1-16 

353 

9-556 

140*47 

1-83 

311 

5-379 

79-07 

1-16 

354 

9-680 

142-30 

1-82 

312 

5-458 

80-23 

1-18 

355 

9-804 

14412 

1-84 

313 

5-538 

81*41 

1-19 

356 

9-929 

145-96 

1-85 

314 

5-619 

82-60 

1-20 

357 

10*055 

147-81 

1-87 

315 

5-701 

83-80 

1-22 

358 

10-182 

149-68 

1-89 

316 

5784 

85*02 

1-22 

359 

10-311 

151-57 

1-93 

317 

5-867 

86-24 

1-24 

360 

10-442 

153-50 

1-95 

318 

5-951 

87-48 

1-23 

361 

10-575 

155-45 

1-99 

319 

6-035 

88-71 

1-27 

362 

10-710 

157-44 

2-01 

320 

6-121 

89-98 

1-28 

363 

10*847 

159-45 

2-03 

321 

6-208 

91-26 

1-29 

364 

10-985 

161-48 

2-03 

322 

6-296 

92-55 

1-31 

865 

11-123 

163-51 

2-04 

323 

6-385 

93-86 

1-32 

366 

11-262 

165-55 

2-04 

324 

6-475 

95-18 

1-34 

367 

11*401 

167-59 

2-08 

325 

6-556 

96-42 

1-35 

368 

11-542 

169-67 

2-08 

326 

6-658 

97-87 

1-37 

369 

11-684 

171-75 

2-14 

327 

6-751 

99-24 

1-40 

370 

11-829 

173-89 

2-16 

328 

6-846 

100-64 

1*45 

371 

11 976 

... % 

17605 

2*19 

j- ■ i *!• f 


2 I 


45 












































530 


THE ENGINEER’S HANDY-BOOK. 
TABLE — ( Continued .) 


Temp. 

Fah. 

Pressures 
in Atmos¬ 
pheres. 

Pressures 
in Lbs. per 
Sq. Inch. 

Differ¬ 

ences. 

Temp. 

Fah. 

Pressures 
in Atmos¬ 
pheres. 

Pressures 
in Lbs. per 
Sq.Inch. 

Differ¬ 

ences. 

372 

12 T 25 

178-24 

2*19 

387 

14-510 

213-30 

2-51 

373 

12274 

180-43 

2-22 

388 

14-681 

215-81 

2-54 

374 

12-425 

182-65 

2-22 

389 

14-854 

218-35 

2-58 

375 

12-576 

184-87 

2-23 

390 

15-029 

22093 

2*60 

376 

12-728 

187-10 

2*25 

391 

15-206 

223-53 

2-56 

377 

12-881 

18935 

2-26 

392 

15-380 

226-09 

2-13 

378 

13-035 

19 T 61 

2-28 

393 

15-457 

227-22 

2-64 

379 

13-190 

193-86 

2-31 

394 

15-637 

229-86 

2-69 

380 

13-347 

196-20 

2-35 

395 

15-820 

232-55 

2-65 

381 

13-507 

198-55 

2'40 

396 

16-000 

235-20 

2-79 

382 

13-670 

200-95 

2-44 

397 

16-190 

237-99 

2-87 

383 

13-836 

203-39 

2-45 

398 

16-385 

240-86 

290 

384 

14*003 

205-84 

2-47 

399 

16-582 

243-76 

2-94 

385 

14-171 

208-31 

2-49 

400 

16-782 

246-70 

3-04 

386 

14-340 

21080 

2*50 






Oases. 

All substances, whether animal, vegetable, or mineral, consisting 
of carbon, hydrogen, aud oxygen, when exposed to a red heat, 
produce various inflammable elastic fluids capable of furnishing 
artificial light. The products of perfect combustion are gases 
which form in accordance with unchangeable laws. Many of the 
gases have already been brought into the liquid state by the con¬ 
joint agency of cold and compression, and all of them are proba¬ 
bly susceptible of a similar reduction by the use of means suffi¬ 
ciently powerful for the required end. They must consequently 
be regarded as the superheated steams or vapors of the liquids 
into which they are compressed. 

When a gas or vapor is compressed into half its original bulk, 
its pressure is double; when compressed into a third of its original 
bulk, its pressure is trebled ; when compressed into a fourth of its 
original bulk, its pressure is quadrupled; and generally the press¬ 
ure varies inversely as the bulk into which the gas is compressed. 
So in like manner, if the volume be doubled, the pressure is made 






















THE ENGINEER^ HANDY-BOOK. 


531 


one-half of what it was before,— the pressure in every case being 
reckoned from 0, or from a perfect vacuum. 

Thus, if we take the average pressure of the atmosphere at 14‘7 
pounds on the square inch, a cubic foot of air, if suffered to expand 
into twice its bulk, by being placed in a vacuum measuring two 
cubic feet, will have a pressure of 7*35 pounds above a perfect 
vacuum, and also of 7*35 pounds below the atmospheric press¬ 
ure; whereas, if the cubic foot be compressed into a space of 
half a cubic foot, the pressure will become 29*4 pounds above 
a perfect vacuum, and 14*7 above the atmospheric pressure. 
The specific gravity of any one gas to that of another will not 
exactly conform to the same ratio under different degrees of heat, 
and other pressures of the atmosphere. 

Oxygen is the name given to the solid particles of oxygen gas, 
which is a combination of oxygen, caloric, and light, and is the 
simplest form in which oxygen can be obtained. Oxygen is called 
the radical or base of the gas; and the same mode of expression 
is used in other cases. Oxygen enters into chemical combination 
with a great number of substances, in which it exists in a concrete 
or solid state; it is by the application of heat, or of acids, to some 
of the substances containing it, that it is usually procured in the 
form of gas. Oxygen gas is the only one that can be breathed by 
animals for any length of time with impunity. The power of at¬ 
mospheric air in supporting respiration is owing to the oxygen. 
Oxygen combines with all the metals, and in this state they are 
called metallic oxides, depriving them of their metallic lustre, and 
giving them an earthy or rusty appearance. Any of the metals 
are capable of combining with different proportions of oxygen. 
Those with one proportion are called protoxides; of two, deutoxides; 
those of three, tritoxides. 

Nitrogen. —Nitrogen gas is most easily described by including 
many of its negative qualities. It has no taste; it unites with 
oxygen in several proportions; it also unites with hydrogen. 
Though incapable of being breathed above its base, nitrogen is a 
component portion of all animal substances; it is lighter than oxy- 



532 


THE ENGINEER’S HANDY-BOOK. 


gen. Nitrogen gas may be variously obtained. If the oxygen be 
extracted from the atmospheric air, this substance will remain, and 
will generally be very pure, unless the oxygen has been extracted 
by respiration. If iron tilings and sulphur, moistened with water, 
be put into ajar containing atmospheric air, this gas will in a day 
or two be all the air that remains in the jar, as the oxygen will 
be absorbed by the iron and sulphur. Phosphorus or sulphuret 
of lime or potass, inclosed with common air in ajar, will produce 
a similar effect. 

Hydrogen. —Hydrogen, like oxygen and nitrogen, is invisible, 
elastic, and inodorous; but the last quality it seldom possesses, be¬ 
cause it is very seldom perfectly dry, and when it contains water 
in solution, like alkaline sulphurets, its odor is considerably fetid. 
Hydrogen with oxygen forms water; and it is by the decomposi¬ 
tion of water that chemists obtain it in the greatest abundance 
and purity. For this purpose iron filing or turnings, or granu¬ 
lated zinc, are put into a retort, and covered with sulphuric acid 
diluted with four times its weight in water. A violent effervescence 
ensues, a large quantity of gas is evolved, and issuing from the 
retort is collected in the usual manner by the pneumatic appa¬ 
ratus. In this experiment the acid is not decomposed; it is the 
oxygen of the water with which the acid is diluted that seizes upon 
and oxidizes the metal, and the hydrogen, in the same portion of 
water being thus disengaged, passes over in the state of gas. The 
hydrogen obtained by using zinc is the purest, that obtained by 
using iron generally containing some carbon. 

Hydrogen combines with a larger quantity of oxygen than any 
other, body; its combustion, therefore, when mixed with oxygen, 
produces a more intense heat than any other combustion. 

Carbon. — Vegetables, when burnt or distilled in close vessels 
till their volatile parts are entirely separated, leave a black, brittle 
and cinereous substance which constitutes the greater part of the 
woody fibre, and is called charcoal. Charcoal contains a portion 
of earthy and saline impurities, but, when entirely freed from these 
and other impurities, a solid, simple, combustible substance 


THE ENGINEER’S HANDY-BOOK. 533 

mains, which is called carbon. Carbon exists naturally in a state 
of greater purity than can be prepared by art. The diamond is 
pure carbon crystallized, aud when pure is colorless and transpa¬ 
rent. It is the hardest substance known; and, as it sustains a 
considerable degree of heat unchanged, it was formerly considered 
to be incombustible. It may, however, be consumed by a burning- 
glass, and even by the heat of a furnace. The difficulty of burning 
it appears to arise from its hardness; for Morveau and Tennant 
have rendered common charcoal so hard, by exposing it for some 
time to a violent fire in close vessels, that it endured a red heat 
without catching fire. Common charcoal contains only 64 parts 
of diamond, or pure carbon, and 36-of oxygen in every 100. 

The common charcoal of commerce is usually prepared from 
young wood, which is piled up near the place where it is cut in 
conical heaps, covered with earth, and burnt with the least pos¬ 
sible access of air. When the fire is supposed to have penetrated 
to the centre of the thickest pieces, it is extinguished by entirely 
closing the vents. When charcoal is wanted very pure, the pro¬ 
duct of this mode of preparing it will not suffice; for the manu¬ 
facturing of the best gunpowder, it is distilled in iron cylinders. 
Chemists prepare it in small quantities in a crucible covered with 
sand, and after they have thus prepared it, they pound it, and 
wash away the salts it contains by muriatic acid ; the acid is re¬ 
moved by the plentiful use of water, and afterwards the charcoal 
is exposed to a low red heat. Pure charcoal is perfectly tasteless 
and insoluble in water. 

Charcoal newly prepared absorbs moisture with avidity. It 
also absorbs oxygen and other gases, which are condensed in its 
pores in quantity many times exceeding its own bulk, and which 
are given out unaltered. Fresh charcoal allowed to cool without 
exposure to air, and the gas then admitted, will absorb 2*25 times 
its bulk of atmospheric air immediately, and 75 per cent, more 
in four or five hours; of oxygen gas about 1*8 immediately, and 
slowly one more; of nitrogen gas, 1'65 immediately. 

45 * 


534 


THE ENGINEER’S HANDY-BOOK. 


Technical and Chemical Terms as Applied to Substances 
that hear Relations to the Steam-Engine both in Theory 
and Practice. 

Alkali, or antacid, means any substance which, when mingled 
with acid, produces fermentation. 

Ammonia. —This alkali, when perfectly caustic, enables chem¬ 
ists to distinguish between the salts of lime and those of magnesia, 
as it precipitates the earth from the latter salts, but not from the 
former. 

Analysis means resolution, by chemistry, of any matter into its 
primary and constituent parts. 

Atoms. —In the chemical combination of bodies with each 
other, it is observed that some unite in all proper proportions; 
others in all proportions as far as a certain point beyond which 
combination no longer takes place. There are also many examples 
in which they unite in one proportion only, and others in several 
proportions; and these proportions are definite, and in the inter¬ 
mediate ones no combination ensues. 

Bases. — This term is usually applied to alkalies, earths, and 
metallic oxides in their relations to the acids and salts. It is 
sometimes also applied to the particular constituents of an acid 
or oxide, on the supposition that the substance combined with the 
oxygen, etc., is the basis of the compound to which it owes its 
particular qualities. 

Calcination. —This term is applied to the fixed residues of 
such matters as have undergone combustion, and are called cin¬ 
ders in common language, and oxides by chemists. This opera¬ 
tion, when considered with regard to these residues, is termed 
calcination. 

Combination is understood to be the intimate union of the par- 


THE ENGINEER’S HANDY-BOOK. 535 

tides of different substances by chemical attraction, so as to form 
a compound possessed of new and peculiar properties. 

Compound. — A compound is the result or effect of a compo¬ 
sition of different things, or that which arises from them. It 
stands opposed to simple. 

Equivalents are terms introduced into chemistry to express the 
system of definite ratios in which the molecular atoms of this sci¬ 
ence reciprocally unite. 

Evaporation is a chemical process usually performed by apply¬ 
ing heat to any compound substance, in order to dispel the vola¬ 
tile parts. 

Fixed. —This epithet is applied to such bodies as so far resist 
the action of heat so as not to rise in vapor. It is the opposite 
of volatile; but it must be observed that the fixity of bodies is 
merely a relative term, as an adequate degree of heat will dissi¬ 
pate all. 

Neutral. —A term applied to saline compounds of an acid or 
alkali nature, which are so called, because they do not possess the 
characters of acid or alkaline salts. 

Neutralization. —This term is applied when acid and alkaline 
matter are combined in such proportion that the compound does 
not change the color of litmus or violets, in which condition they 
are said to be neutralized. 

Oxide. — Any substance which combines with oxygen without 
being in the state of an acid is an oxide. 

Oxidation. —This term is applied to the process of converting 
metals and other substances into oxides by combining with them a 
certain portion of oxygen. 

Phosphate is a salt formed by the union of phosphoric acid 



536 the engineer’s handy - book . 

with salifiable bases ; thus, phosphate of ammonia, phosphate of 
lime, etc. 

Pyrites. —Substances which strike fire when rubbed or thrown 
together. They are frequently found in bituminous coal, and often 
induce spontaneous combustion. 

Saline. — A term applied to any substance of a salty nature. 
The number of saline substances is very considerable, and they 
possess peculiar characters by which they are distinguished from 
other substances. 

Saturation. — A term applied to bodies which have a chemical 
affinity for each other, and which will only unite in certain pro¬ 
portions. When, therefore, a fluid has dissolved as much of any 
substance as it is capable of dissolving, it is said to have reached 
the point of saturation. Thus, water will dissolve one-quarter of 
its weight of common salt, and if more salt be added, it will sink 
to the bottom in a solid state. 

Areas of Circles. 

The term area means any opening or flat surface confined be¬ 
tween any lines; a definite space; superficial contents of any fig¬ 
ure ; any plain space or surface included within any given lines; 
but when used in connection with the steam-engine, it means the 
number of square inches in the piston, or valve, against which the 
steam acts, as the case may be. 

A circle may be considered as composed of many triangles, 
whose bases are the circumference of the circle, and whose vertices 
are coincident with the centre of the circle. If a cylinder be 
drawn, whose height equals l its diameter, the convex surface of 
such a cylinder is just equal to the area of the circle. A circular 
vessel will contain a greater quantity than a vessel of any other 
shape made of the same amount of material. The areas of cir¬ 
cles are to each other as the square of their diameters. The di¬ 
ameter of a circle being 1, its circumference equals 3T416. 



THE ENGINEER’S HANDY-BOOK. 537 

The diameter of a circle is a straight line drawn 
through its centre, touching both sides, thus. 

The radius of a circle is half the diameter. 

A chord is a straight line joining any two places in 
the circumference of a circle. 

The versed sine is a perpendicular joining the middle 
of the chord and circumference of a circle. 

An arc is any part of the circumference of a circle... 

A triangle has 3 sides and 3 angles. 





A parallelogram has 4 sides and 4 angles 


A pentagon has 5 sides and 5 angles 


A hexagon has 6 sides and 6 angles 


A heptagon has 7 sides and 7 angles 



An octagon has 8 sides and 8 angles 





















538 


THE ENGINEER’S HANDY-BOOK. 


A nonagon has 9 sides and 9 angles 



A decagon has 10 sides and 10 angles 



An endecagon has 11 sides and 11 angles 



A dodecagon has 12 sides and 12 angles 



Rules. 

To find the circumference of a circle, multiply the diameter by 
3’1416 ; the product is the circumference. 

To find the diameter of a circle, divide the circumference by 
3-1416, the quotient is the diameter ; or multiply the square root 
of the area by 1-12837, the product is the diameter. 

To find the area of a circle, multiply the square of the diam¬ 
eter by '7854, the product is the area; or multiply half the cir¬ 
cumference by half the diameter, the product is the area; or mul¬ 
tiply the diameter by the circumference, and divide by 4; the 
quotient is the area. 

To find the area of an ellipse or oval, multiply the long di¬ 
ameter by the short diameter; multiply this product by *7854, 
and the product will be the superficial area of the ellipse. 

To find the circumference of an ellipse or oval, multiply 4 
the sum of the two diameters by 3T416; the product will be the 
circumference of the ellipse. 

To find the area of a parallelogram, multiply the length by the 
height or perpendicular breadth. 

To find the area of a triangle, multiply the base by the perpen¬ 
dicular height, and take half the product. 






THE ENGINEER’S HANDY - BOOK . 


539 


To find the area of a trapezoid, multiply half the sum of the 
parallel sides by the perpendicular distance between them; the 
product will be the area. 

To find the area of a quadrilateral inscribed in a circle.—From 
half the sum of the four sides subtract each side severally; mul¬ 
tiply the four remainders together ; the square root of the product 
is the area. 

To find the area of any quadrilateral figure, divide the quadri¬ 
lateral into two triangles; the sum of the areas of the triangles is 
the area. 

To find the area of any polygon, divide the polygon into trian¬ 
gles and trapezoids by drawing diagonals ; find the areas of these, 
as above shown, for the area. 

To find the area of a regular polygon, multiply half the per¬ 
imeter of the polygon by the perpendicular drawn from the centre 
to the centre of one of the sides. 

To find the area of a sector of a circle, multiply half the length 
of the arc of the sector by the radius. Or, multiply the number 
of degrees in the arc by the square of the radius, and by *008727. 

To find the area of a segment of a circle, find the area of the 
sector which has the same arc as the segment; also the area of the 
triangle formed by the radial sides of the sector and the chord 
of the arc; the difference or the sum of these areas will be the 
area of the segment, according as it is less or greater than a semi¬ 
circle. 

To find the area of a cycloid, multiply the area of the generat¬ 
ing circle by 3. 

To find the length of an arc of a parabola cut off by a double 
ordinate to the axis. — To the square of the ordinate add four- 
fifths of the square of the absciss ; twice the square root of the 
sum is the length nearly. 

To find the area of an ellipse, multiply the product of the two 
axes by *7854. 

To find the area of an elliptic segment, the base of which is 
parallel to either axis of the ellipse. — Divide the height of the 


540 


THE ENGINEER’S HANDY-BOOK. 


segment by the axis of which it is a part, and find the area of a 
circular segment, which the height is equal to in this quotient; 
multiply the area thus found by the two axes of the ellipse suc¬ 
cessively ; the product is the area. 

To find the length of an arc of a hyperbola beginning at the 
vertex. — To nineteen times the transverse axis, add twenty-one 
times the parameter to this axis, and multiply the sum by the 
quotient of the absciss divided by the transverse. 

To find the area of a hyperbola, to the product of the trans¬ 
verse and absciss add five-sevenths of the square of the absciss, 
and multiply the square root of the sum by twenty-one; to this 
product add four times the square root of the product of the trans¬ 
verse and absciss ; multiply the sum by four times the product of 
the conjugate and absciss, and divide by seventy-five times the 
transverse. The quotient is the area nearly. 

To find the surface of a prism or a cylinder, the perimeter of 
the end multiplied by the height gives the upright surface; add 
twice the area of an end. 

To find the cubic contents of a prism or a cylinder, multiply 
the area of the base by the height. 

To find the surface of a pyramid or a cone, multiply the per¬ 
imeter of the base by half the slant height, and add the area of 
the base. 

To find the cubic contents of a pyramid or a cone, multiply the 
area of the base by one-third of the perpendicular height. 

To find the surface of a frustum of a pyramid or a cone, mul¬ 
tiply the sum of the perimeters of the ends by half the slant 
height, and add the areas of the ends. 

To find the cubic contents of a frustum of a pyramid or a 
cone, add together the areas of the two ends, and the mean pro¬ 
portional between them (that is, the square root of their pro¬ 
duct), and multiply the sum by one-third of the perpendicular 
height. 

To find the cubic contents of a segment of a sphere, from three 
times the diameter of the sphere subtract twice the height of the 


THE ENGINEER’S HANDY-BOOK. 


541 


segment; multiply the difference by the square of the height, 
and by '5236. 

To find the cubic contents of a frustum or zone of a sphere. — 
To the sum of the squares of the radii of the ends add one-third 
of the square of the height; multiply the sum by the height and 
by 1*5708. 

To find the cubic contents of a spheroid, multiply the square 
of the revolving axis by the fixed axis and by '5236. 

To find the cubic contents of a segment of a spheroid.—When 
the base is parallel to the revolving axis, multiply the difference 
between thrice the fixed axis and double the height of the segment 
by the square of the height, and the product by '5236. 

To find the cubic contents of a wedge. — To twice the length of 
the base add the length of the edge; multiply the sum by the 
breadth of the base, and by one-sixth of the height. 

To find the cubic contents of a prismoid (a solid of which the 
two ends are dissimilar, but parallel plane figures of the same 
number of sides).— To the sum of the areas of the two ends, add 
four times the area of a section parallel to and equally distant 
from both ends; and multiply the sum by one-sixth of the length. 

To find the surface of a sphere, multiply the square of the di¬ 
ameter by 3T416. 

To find the curve surface of any segment or zone of a sphere, 
multiply the diameter of the sphere by the height of the zone or 
segment and by 3T416. 

To find the cubic contents of a sphere, multiply the cube of 
the diameter by '5236. 

To find the cubic contents of a parabolic conoid, multiply the 
area of the base by half the height. 

To find the cubic contents of a frustum of a parabolic conoid, 
multiply half the sum of the areas of the two ends by the height 
of the frustum. 

46 




542 


THE ENGINEER’S HANDY-BOOK. 


Signification of Signs Used in Calculations. 


— 

signifies Equality, 

as 

3 added to 2 — 5. 

+ 

« 

Addition, 


4 + 2 = 6. 

— 

u 

Subtraction, 

u 

7 — 4 = 3. 

X 

(( 

Multiplication, 

« 

6 x 2 = 12. 

• 

(( 

Division, 

« 

16 -5- 4 = 4. 

• • 

• • 

. . t< 

• m 

Proportion, 

ti 

2 is to 3 so is 4 to 6. 

v/ 

it 

Square Root, 

u 

v/16 = 4. 

4/ 

u 

Cube Root, 

u 

4/64 = 4. 

3 2 

u 

3 is to be squared, 

u 

3 2 = 9. 

3 3 

« 

3 is to be cubed, 

(t 

• 

t- 

CM 

1! 

CO 

CO 

2+ 5x4 

= 28 signifies that two, 

three, or more numbers 



are to be taken together, as 2 + 5 = 7, and 



4 times 7 = 28. 




+, plus, means that the number after it is to be added to the 
number before it; thus, 5 + 4 are 9. 

—, minus, means that the number after it is to be subtracted 
from the number before it; thus, 5 — 4 is 1. 

X, multiplied by, means that the number before it is to be mul- 
tip)lied by the number after it; thus, 9x3 are 27. 

-T-, divided by, means that the number before it is to be divided 
by the number after it; thus, 9-5-3 are 3. 

—, equal to, means that the quantity after it is of the same 
value as the quantity before it; thus, 5 + 6 = 11. 


The Cipher. 

The term Cipher has various meanings. It is usually applied 
to the figure 0, which is equivalent to zero, or nothing. It also 
means a combination or intertexture of letters, as the initials of 
a name, the several letters being intertwined so as to form one 
figure. The word cipher also means secret writing; the proper 
name for which, however, is cryptogram. 


THE ENGINEER’S HANDY-BOOK 


543 


TABLE 


OF DIAMETERS AND AREAS OF SMALL CIRCLES. 


Diam. 

Area. 

Diam. 

Area. 

Diam. 

Area. 

•001 

•0000008 

•027 

•0005726 

•0625 

•0030680 

•002 

•0000031 

•028 

•0006158 

•065 

•0033183 

•003 

•0000071 

•029 

•0006605 

•070 

•0038485 

•004 

•0000126 

•030 

•0007069 

•075 

•0044179 

•005 

•0000196 

•031 

•0007548 

•080 

•0050266 

•006 

•0000283 

•03125 

•0007670 

•085 

•0056745 

•007 

•0000385 

•032 

•0008043 

•090 

•0063617 

•008 

•0000503 

•033 

•0008553 

•095 

•0070882 

•009 

•0000639 

•034 

•0009079 

•100 

•0078540 

•010 

•0000785 

•035 

•0009621 

•125 

•0122719 

•Oil 

♦0000950 

•036 

•0010179 

•150 

•0176715 

•012 

•0001131 

•037 

•0010752 

*200 

•0314159 

•013 

•0001327 

•038 

•0011341 

•250 

•0490875 

•014 

•0001539 

•039 

•0011946 

•300 

•0706858 

•015 

•0001767 

•040 

•0012566 

•350 

•0962115 

•015625 

•0001917 

•041 

•0013203 

•400 

•1256637 

•016 

•0002016 

•042 

•0013855 

•450 

•1590435 

•017 

•0002270 

•043 

•0014522 

•500 

•1963495 

•018 

•0002545 

•044 

•0015205 

•550 

•2375835 

•019 

•0002835 

•045 

•0015904 

•600 

•2827440 

•020 

•0003142 

•046 

*0016619 

•650 

•3318315 

•021 

•0003464 

•047 

0017349 

*700 

•3848441 

•022 

•0003801 

•048 

•0018096 

•750 

•4417875 

023 

•0004155 

•049 

•0018857 

•800 

•5026548 

•024 

•0004524 

•050 

•0019635 

•850 

•5674515 

•025 

•0004909 

•055 

•0023758 

•900 

•6361725 

•026 

•0005309 

•060 

•0028274 

•950 

•7088235 
























544 


THE ENGINEER’S HANDY-BOOK. 

TABLE 

CONTAINING THE DIAMETERS, CIRCUMFERENCES, AND AREAS OF 
CIRCLES FROM y*g- OF AN INCH TO 100 INCHES, ADVANCING BY 
T V OF AN INCH UP TO 10 INCHES, AND BY | OF AN INCH FROM 
10 TO 100 INCHES. 


Diam. 

ClRCUM. 

V 

Area. 

Diam. 

ClRCUM. 

Area. 

Inch. 


- 

Inch. 



T¥ 

.1963 

.0030 

t't 

7.6576 

4.6664 

i 

.3927 

.0122 


7.8540 

4.9087 

T 3 6 

.5890 

.0276 

9 

1 s 

8.0503 

5.1573 

* 

. .7854 

.0490 

A 

8 

8.2467 

5.4119 

tV 

.9817 

.0767 

1 1 

T¥ 

8.4430 

5.6727 

a 

8 

1.1781 

.1104 

4 

8.6394 

5.9395 

tV 

1.3744 

.1503 

1 3 

T6 

8.8357 

6.2126 

* 

1.5708 

.1963 

7 

8 

9.0321 

6.4918 

T6 

1.7671 

.2485 

X 5 

T¥ 

9.2284 

6.7772 

1 

1.9635 

.3068 

3 

9.4248 

7.0686 

To 

2.1598 

.3712 

TT 

9.6211- 

7.3662 

3 

4 

2.3562 

.4417 

i 

9.8175 

7.6699 

1 3 

1.6 

2.5525 

.5185 

TT 

10.0138 

7.9798 

7 

8 

2.7489 

.6013 

1 

4 

10.2120 

8.2957 

1 5 

IT 

2.9452 

.6903 

5 

T¥ 

10.4065 

8.6179 

1 

3.1416 

.7854 

3 

8 

10.6029 

8.9462 

T*T 

3.3379 

.8861 

TT 

10.7992 

9.2806 

1 

3.5343 

.9940 

i 

10.9956 

9.6211 

TT 

3.7306 

1.1075 

T¥ 

11.1919 

9.9678 

1. 

4 

3.9270 

1.2271 

1 

11.3883 

10.3206 

5 

To 

4.1233 

1.3529 

11 

T¥ 

11.5846 

10.6796 

3 

8 

4.3197 

1.4848 

a. 

4 

11.7810 

11.0446 

tV 

4.5160 

1.6229 

1 3 

TT 

11.9773 

11.4159 

? 

4.7124 

1.7671 

7 

H 

12.1737 

11.7932 

TT 

4.9087 

1.9175 

X 5 

TT 

12.3700 

12.1768 

5 

8 

5.1051 

2.0739 

4 

12.5664 

12.5664 

1 X 

TT 

5.3014 

2.2365 

TT 

12.7627 

12.9622 

3 

4 

5.4978 

2.4052 

i 

12.9591 

13.3640 

13 

1 0 

5.6941 

2.5801 

tV 

13.1554 

13.7721 

7 

F 

5.8905 

2.7611 

i 

13.3518 

14.1862 

1 5 

TT 

6.0868 

2.9483 

A 

13.5481 

14.6066 

2 

6.2832 

3.1416 

A 

8 

13.7445 

15.0331 

tV 

6.4795 

3.3411 

TT 

13.9408 

15.4657 


6.6759 

3.5465 

¥ 

14.1372 

15.9043 

A 

6.8722 

3.7582 

T¥ 

14.3335 

16.3492 


7.0686 

3.9760 

A 

8 

14.5299 

16.8001 

fr 

7.2640 

4.2001 

H 

14.7262 

17.2573 

3 

¥ 

7.4613 

4.4302 

1 

14.9226 

17.7205 




















545 


THE ENGINEER’S HANDY-BOOK. 

TABLE — ( Continued) 

CONTAINING THE DIAM., CIRCUMFERENCES, AND AREAS OF CIRCLES. 


Diam. 

ClRCUM. 

Area. 

Diam. 

ClRCUM. 

Area. 

Inch. 

1 3 

f 

¥ 

it 

5 
^6 

A 

i 

t 5 ¥ 

3 

8 

Te- 

i 

9 

¥ 

i i 

TO 

a 

4 

1 3 

TO 

7 
¥ 

1 5 

TO 

6 

t 

T¥ 

i 

3 

8 

T¥ 

i 

9 

¥- 

8 

it 

a 

4 

1 3 

¥ 

¥ 

1 5 

T¥ 

7 

tV 

i 

t 

_ 6 _ 

a 6 

8 

15.1189 

15.3153 

15.5716 

15.7080 

15.9043 

16.1007 

16.2970 

16.4934 

16.6897 

16.8861 

17.0824 

17.2788 

17.4751 

17.6715 

17.8678 

18.0642 

18.2605 

18.4569 

18.6532 

18.8496 

19.0459 

19.2423 

19.4386 

19.6350 

19.8313 

20.0277 

20.2240 

20.4204 

20.6167 

20.8131 

21.0094 

21.2058 

21.4021 

21.5985 

21.7948 

21.9912 

22.1875 

22.3839 

22.5802 

22.7766 

22.9729 

23.1693 

18.1900 

18.6655 

19.1472 

19.6350 

20.1290 

20.6290 

21.1252 
21.6475 
22.1661 
22.6907 
23.2215 
23.7583 
24.3014 
24.8505 
25.4058 
25.9672 
26.5348 
27.1085 
27.6884 
28.2744 
28.8665 
29.4647 
30.0798 
30.6796 
31.2964 
31.9192 
32.5481 
33.1831 
33.8244 
34.4717 

35.1252 
35.7847 
36.4505 
37.1224 
37.8005 
38.4846 
39.1749 
39.8713 
40.5469 
41.2825 
41.9974 
42.7184 

Inch. 

ft 

* 

9 

¥ 

H 

a 

4 

I 3 

To 

7 
¥ 

it 

8 

t 

i 

f 

A 

9 

¥ 

II 

T6 

a 

4 

i# 

1_6 

7 
¥ 

1 5 

T¥ 

9 

TO 

i 

To 

i 

❖ 

8 

l¥ 

i 

1 9 0 

t 

it 

a 

4 

1 3 

¥ 

¥ 

1 5 

T¥ 

10 

23.3656 

23.5620 

23.7583 

23.9547 

24.1510 

24.3474 

24.5437 

24.7401 

24.9364 

25.1328 

25.3291 

25.5255 

25.7218 

25.9182 

26.1145 

26.3109 

26.5072 

26.7036 

26.8999 

27.0963 

27.2926 

27.4890 

27.6853 

27.8817 

28.0780 

28.2744 

28.4707 

28.6671 

28.8634 

29.0598 

29.2561 

29.4525 

29.6488 

29.8452 

30.0415 

30.2379 

30.4342 

30.6306 

30.8269 

31.0233 

31.2196 

31.4160 

43.4455 

44.1787 

44.9181 

45.6636 

46.4153 

47.1730 

47.9370 

48.7070 

49.4833 

50.2656 

51.0541 

51.8486 

52.8994 

53.4562 

54.2748 

55.0885 

55.9138 

56.7451 

57.5887 
58.4264 
59.7762 
60.1321 
60.9943 
61.8625 
62.7369 
63.6174 
64.5041 
65.3968 
66.2957 
67.2007 
68.1120 
69.0293 
69.9528 
70.8823 
71.8181 
72.7599 
73.7079 
74.6620 
75.6223 

76.5887 
77.5613 
78.5400 


40* 2 Iv 






















546 


THE ENGINEER’S HANDY-BOOK. 


TABLE — ( Continued) 

CONTAINING THE DIAM., CIRCUMFERENCES, AND AREAS OF CIRCLES. 


Diam. 

ClRCUM. 

Area. 

Diam. 

ClRCUM. 

Area. 

Inch. 

£ 

31.8087 

80.5157 

Inch. 

2. 

g 

48.3021 

185.6612 

£ 

32.2014 

82.5160 

£ 

48.6948 

188.6923 

3 

8 

32.5941 

84.5409 

t 

49.0875 

191.7480 

£ 

32.9868 

86.5903 

2 

4 

7 

8 

49.4802 

194.8282 

1 

33.3795 

88.6643 

49.8729 

197.9330 

£ 

4 

33.7722 

90.7627 

16 

50.2656 

201.0624 

7 

8 

34.1649 

92.8858 

£ 

50.6583 

204.2162 

11 

34.5576 

95.0334 

£ 

51.0510 

207.3946 

* 

34.9503 

97.2053 

3 

¥ 

51.4437 

210.5976 

£ 

35.3430 

99.4021 


51.8364 

213.8251 

3 

8 

35.7357 

101.6234 

¥ 

52.2291 

217.0772 

4 

36.1284 

103.8691 

f 

52.6218 

220.3537 

1 

36.5211 

106.1394 | 

7 

¥ 

53.0145 

223.6549 

4 

36.9138 

108.4342 

17 

53.4072 

226.9806 

$ 

37.3065 

110.7536 

i 

53.7999 

230.3308 

12 

37.6992 

113.0976 

£ 

54.1926 

233.7055 

* 

38.0919 

115.4660 

i 

8 

54.5853 

237.1049 

£ 

38.4846 

117.8590 

£ 

54.9780 

240.5287 

8 

38.8773 

120.2766 

1 

55.3707 

243.9771 

£ 

39.2700 

122.7187 

4 

55.7634 

247.4500 

t 

39.6627 

125.1854 

¥ 

56.1561 

250.9475 

A 

4 

40.0554 

127.6765 

18 

56.5488 

254.4696 

£ 

40.4481 

130.1923 

£ 

56.9415 

258.0161 

13 

40.8408 

132.7326 

£ 

57.3342 

261.5872 

i 

41.2338 

135.2974 

3 

8 

57.7269 

265.1829 

£ 

41.6262 

137.8867 

£ 

58.1196 

268.8031 

3 

8 

42.0189 

140.5007 

5 

¥ 

58.5123 

272.4479 

A 

42.4116 

143.1391 

£ 

58.9056 

276.1171 

' I 

8 

42.8043 

145.8021 

7 

¥ 

59.2977 

279.8110 

3 

¥ 

i 

43.1970 

148.4896 

19 

59.6904 

283.5294 

43.5897 

151.2017 

£ 

60.0831 

287.2723 

14 

43.9824 

153.9384 

£ 

60.4758 

291.0397 

* 

44.3751 

156.6995 

s 

8 

60.8685 

294.8312 

£ 

44.7676 

159.4852 

£ 

61.2612 

298.6483 

8 

45.1605 

162.2956 

5 

8 

61.6539 

302.4894 

£ 

45.5532 

165.1303 

a. 

4 

62.0466 

306.3550 

1 

45.9459 

167.9896 

7 

¥ 

62.4393 

310.2452 

a. 

4 

46.3386 

170.8735 

20 

62.8320 

314.1600 

7 

¥ 

46.7313 

173.7820 

£ 

63.2247 

318.0992 

15 

47=1240 

176.7150 

£ 

63.6174 

322.0630 

* 

47.5167 

179.6725 

3 

8 

64.0101 

326.0514 

* 

47.9094 

182.6545 

£ 

64.4028 

330.0643 




















TABLE — ( Continued ) 


CONTAINING THE DIAM., CIRCUMFERENCES, AND AREAS OF CIRCLES. 


Diam. 

ClRCUM. 

Area. 

Diam. 

ClRCUM. 

Area. 

Inch. 



Inch. 



5 

64.7955 

*334.1018 

1 

81.2889 

525.8375 

| 

65.1882 

338.1637 

26 

81.6816 

530.9304 

7 

F 

65.5809 

342.2503 

i 

82.0743 

536.0477 

21 

65.7936 

346.3614 

i 

82.4670 

541.1896 

* 

66.3663 

350.4970 

3 

8 

82.8597 

546.3561 

i 

66.7590 

354.6571 

2 

83.2524 

551.5471 

1 

67.1517 

358.8419 


83.6451 

556.7627 


67.5444 

363.0511 

3 

84.0378 

562.0027 


67.9371 

367.2849 

I 

84.4305 

567.2674 

| 

68.3298 

371.5432 

27 

84.8232 

572.5566 


68.7225 

375.8261 

i 

85.2159 

577.8703 

22 

69.1152 

380.1336 

i 

85.6086 

583.2085 

& 

69.5079 

384.4655 

1 

86.0013 

588.5714 

* 

69.9006 

388.8220 

2 

86.3940 

593.9587 

I 

70.2933 

393.2031 

1 

86.7867 

599.3706 


70.6860 

397.6087 

f 

87.1794 

604.8070 


71.0787 

402.0388 

i 

87.5721 

610.2680 

4 

71.4714 

406.4935 

28 

87.9648 

615.7536 

i 

71.8641 

410.9728 

i 

88.3575 

621.2636 

23 

72.2568 

415.4766 

i 

88.7502 

626.7982 

i 

72.6495 

420.0049 

1 

89.1429 

632.3574 

£ 

73.0422 

424.5577 

i 

89.5356 

637.9411 

f 

73.4349 

429.1352 

1 

89.9283 

643.5494 

* 

73.8276 

433.7371 


90.3210 

649.1821 


74.2203 

438.3636 

I 

90.7137 

654.8395 


74.6130 . 

443.0146 

29 

91.1064 

660.5214 

1 

75.0057 

447.6992 

i 

91.4991 

666.2278 

24 

75.3984 

452.3904 

i 

91.8918 

671.9587 

i 

75.7911 

457.1150 


92.2845 

677.7143 

i 

76.1838 

461.8642 

£ 

92.6772 

683.4943 

f 

76.5765 

466.6380 

f 

93.0699 

689.2989 


76.9692 

471.4363 

i 

93.4626 

695.1280 


77.3619 

476.2592 

l 

93.8553 

700.9817 

| 

77.7546 

481.1065 

30 

94.2480 

706.8600 

7 

■g* 

78.1473 

485.9785 

1 

94.6407 

712.7627 

25 

78.5400 

490.8750 

i 

95.0334 

718.6900 

| 

78.9327 

495.7960 


95.4261 

724.6419 

i 

79.3254 

500.7415 

* 

95.8188 

730.6183 

3. 

79.7181 

505.7117 


96.2115 

736.6193 


80.1108 

510.7063 

f 

96.6042 

742.6447 

| 

80.5035 

515.7255 

7 

F 

96.9969 

748.6948 

i 

80.8962 

520.7692 

31 

97.3896 

754.7694 


















548 


TIIE ENGINEER'S HANDY-BOOK. 


TABLE — ( Continued) 


CONTAINING THE DIAM., CIRCUMFERENCES, AND AREAS OF CIRCLES. 


Diam. 

ClRCUM. 

Area. 

Diam. 

ClRCUM. 

Area. 

Inch. 



Inch. 



1 

8 

97.7823 

760.8685 

3 

8 

114.2757 

1039.1946 

4 

98.1750 

766.9921 

2 

114.6684 

1046.3941 

A 

8 

98.5677 

773.1404 

t 

115.0611 

1053.5281 

1 

5 

98.9684 

779.3131 

3 

4 

115.4538 

1060.7317 

5 

8 

99.3531 

' 785.5104 

7 

8 

115.8465 

1067.9599 

t 

99.7458 

791.7322 

37 

116.2392 

1075.2126 

7 

8 

100.1385 

797.9786 

i 

8 

116.6319 

1082.4898 

32 

100.5312 

804.2496 

1 

4 

117.0246 

1089.7915 

i 

100.9240 

810.5450 

8 

117.4173 

1097.1179 

i 

101.3166 

816.8650 

i 

117.8100 

1104.4687 

3 

8 

101.7093 

823.2096 

i 

118.2027 

1111.8441 

* 

102.1020 

829.5787 

t 

118.5954 

1119.2440 

1 

102.4947 

835.9724 

7 

8' 

118.9881 

1126.6685 

2. 

4 

102.8874 

842.3905 

38 

119.3808 

1134.1176 

£■ 

103.2801 

848.8333 

1 

8 

119.7735 

1141.5911 

33 

103.6728 

855.3006 

JL 

4 

120.1662 

1149.0892 

i 

8 

t 

104.0655 

861.7924 

H 

8 

120.5589 

1156.6119 

104.4582 

868.3087 

£ 

120.9516 

1164.1591 

3 

8 

104.8509 

874.8497 

I 

121.3443 

1171.7309 

¥ 

105.2436 

881.4151 

3. 

4 

121.7370 

1179.3271 

1 

105.6363 

888.0051 

7 

¥ 

122.1297 

1186.9480 

a 

4 

106.0290 

894.6196 

39 

122.5224 

1194.5934 

7 

¥ 

106.4217 

901.2587 

1 

8 

122.9151 

1202.2633 

34 

106.8144 

907.9224 

i 

123.3078 

1209.9577 

i 

8 

107.2071 

914.6105 

i 

123.7005 

1217.6768 

4 

107.5998 

921.3232 

i 

124.0932 

1225.4203 

3 

8 

107.9925 

928.0605 

1 

124.4859 

1233.1884 

4 

108.3852 

934.8223 

i 

124.9787 

1240.9810 

5 

# 

108.7779 

941.6086 

7 

8 

125.2713 

1248.7982 

3. 

4 

109.1706 

948.4195 

40 

125.6640 

1256.6400 

7 

¥ 

109.5633 

955.2550 

¥ 

126.0567 

1264.5062 

35 

109.9560 

962.1150 

£ 

126.4494 

1272.3970 

i 

8 

110.3487 

968.9995 

3 

8 

126.8421 

1280.3124 

I 

4 

110.7414 

975.9085 

£ 

127.2348 

1288.2523 

3 

8 

111.1341 

982.8422 

1 

127.6275 

1296.2168 

1 

? 

111.5268 

989.8003 

I 

128.0202 

1304.2057 

A 

111.9195 

996.7830 

¥ 

128.4129 

1312.2193 

a 

4 

112.3122 

1003.7902 

41 

128.8056 

1320.2574 

7 

¥ 

112.7049 

1010.8-220 

1 

8 

129.1983 

1328.3200 

36 

113.0976 

1017.8784 

£ 

129.5910 

1336.4071 

i 

8 

113.4903 

1024.9592 

3 

8 

129.9837 

1344.5189 

1 

113.8830 

1032.0646 

£ 

130.3764 

1352.6551 



















T PI E ENGINEER’S HANDY-BOOK 


519 


TABLE — ( Continued ) 

CONTAINING THE DIAM., CIRCUMFERENCES, AND AREAS OF CIRCLES. 


Diam. 

ClRCUM. 

Area. 

Diam. 

ClRCUM. 

Area. 

Inch. 

1 

130.7691 

1360.8159 

Inch. 

147.2625 

1725.7324 

3 

f 

F 

131.1618 

1369.0012 

47 

147.6552 

1734.9486 

131.5545 

1377.2111 

1 

8 

148.0479 

1744.1893 

42 

131.9472 

1385.4456 

£ 

148.4406 

1753.4545 

1 

8 

132.3399 

1393.7045 

a 

8 

148.8333 

1762.7344 

£ 

132.7326 

1401.9880 

l 

¥ 

149.2260 

1772.0587 

3 

8 

133.1253 

1410.2961 

5 

8 

149.6187 

1781.3976 

£ 

133.5180 

1418.6287 

a 

4 

150.0114 

1790.7610 

£ 

133.9107 

1426.9859 

¥ 

150.4041 

1800.1490 

3 

J 

F 

134.3034 

1435.3675 

48 

150.7968 

1809.5616 

134.6961 

1443.7738 

1 

8 

151.1895 

1818.9986 

43 

135.0888 

1452.2046 

£ 

151.5822 

1828.4602 

i 

135.4815 

1460.6599 

a 

8 

151.9749 

1837.9364 


135.8742 

1469.1397 

£ 

152.3676 

1847.4571 

a 

8 

136.2669 

1477.6342 

A 

8 

152.7603 

1856.9924 

£ 

136.6596 

1486.1731 

£ 

153.1530 

1868.5521 

f 

137.0523 

1494.7266 

7 

8 

153.5457 

1876.1365 

i 

137.4450 

1503.3046 

49 

153.9384 

1885.7454 

£ 

137.8377 

1511.9072 

£ 

154.3311 

1895.3788 

44 

138.2304 

1520.5344 

£ 

154.7238 

1905.0367 

I 

138.6231 

1529.1860 

¥ 

155.1165 

1914.7093 

£ 

139.0158 

1537.8622 

£ 

155.5092 

1924.4263 

3 

8 

139.4085 

1546.5530 

1 

155.9019 

1934.1579 

£ 

139.8012 

1555.2883 

3 

4 

156.2946 

1943.9140 

1 

140.1939 

1564.0382 

7 

¥ 

156.6873 

1953.6947 

f 

140.5866 

1572.8125 

50 

157.0800 

1963.5000 

7 

¥ 

140.9793 

1581.6115 

1 

8 

157.4727 

1973.3297 

45 

141.3720 

1590.4350 

£ 

157.8654 

1983.1840 

1 

141.7647 

1599.2830 

3 

8 

158.2581 

1993.0529 

£ 

142.1574 

1608.1555 

£ 

158.6508 

2002.9663 

f 

142.5501 

1617.0427 

¥ 

159.0435 

2012.8943 

£ 

142.9428 

1625.9743 

3 

4 

159.4362 

2022.8467 

1 

143.3355 

1634.9205 

7 

¥ 

159.8289 

2032.8238 

£ 

143.7382 

1643.8912 

51 

160.2216 

2042.8254 

7 

IT 

144.1209 

1652.8865 

£ 

160.6143 

2052.8515 

46 

144.5136 

1661.9064 

JL 

4 

161.0070 

2062.9021 

£ 

144.9063 

1670.9507 

3 

¥ 

161.3997 

2072.9764 

1 

4 

145.2990 

1680.0196 

l 

¥ 

161.7924 

2083.0771 

3 

8 

145.6917 

1689.1031 


162.1851 

2093.2014 

i 

¥ 

146.0844 

1698.2311 

a 

4 

162.5778 

2103.3502 

a 

8 

2 

4 

146.4771 

1707.3737 

¥ 

162.9705 

2113.5236 

146.8698 

1716.5407 

52 

163.3632 

2123.7216 

















550 


THE ENGINEER’S HANDY-BOOK. 


TABLE — ( Continued ) 

CONTAINING THE DIAM., CIRCUMFERENCES, AND AREAS OF CIRCLES. 


Diam. 

ClRCUM. 

Area. 

Diam. 

ClRCUM. 

Area. 

Inch. 

i 

163.7559 

2133.9440 

Inch. 

a 

8 

180.2493 

2585.4509 


164.1486 

2144.1910 

i 

¥ 

180.6423 

2596.7287 

a 

8 

164.5413 

2154.4626 

5 

8 

181.0347 

2608.0311 

5 

164.9340 

2164.7587 

a. 

4 

181.4274 

2619.3580 

1 

165.3267 

2175.0794 

¥ 

181.8201 

2630.7095 

A 

4 

7 

8 

165.7194 

2185.4245 

58 

182.2128 

2642.0856 

166.1121 

2195.7943 

i 

182.6055 

2653.4861 

53 

166.5048 

2206.1886 

i 

182.9982 

2664.9112 

i 

166.8975 

2216.6074 

a 

8 

183.3909 

2676.3609 

* 

167.2902 

2227.0507 

? 

183.7836 

2687.8351 


167.6829 

2237.5187 

1 

184.1763 

2699.3338 

£ 

168.0756 

2248.0111 

a 

4 

1845690 

2710.8571 


168.4683 

2258.5281 

7 

¥ 

184.9617 

2722.4050 

£ 

4 

168.8610 

2269.0696 

59 

185.3544 

2733.9774 

7 

¥ 

169.2537 

2279.6357 

i 

185.7471 

2745.5743 

54 

169.6464 

2290.2264 

i 

186.1398 

2757.1957 

i 

170.0391 

2300.8415 

3 

8 

186.5325 

2768.8418 


170.4318 

2311.4812 

1 

21 

186.9252 

2780.5123 

3 

8 

170.8245 

2322.1455 

A 

8 

187.3179 

2792.2074 

* 

171.2172 

2332.8343 

a 

4 

i 

187.7106 

2803.9270 

1 

171.6099 

2343.5477 

188.1033 

2815.6712 

A 

4 

172.0026 

2354.2855 

60 

188.4960 

2827.4400 

7 

¥ 

172.3593 

2365.0480 

i 

188.8887 

2839.2332 

55 

172.7880 

2375.8350 

i 

189.2814 

2851.0510 

i 

173.1807 

2386.6465 

3 

8 

189.6741 

2862.8934 

i 

173.5734 

2397.4825 

i 

190.0668 

2874.7603 

3 

8 

173.9661 

2408.3432 

¥ 

190.4595 

2886.6517 

i 

174.3588 

2419.2283 

a 

4 

190.8522 

2898.5677 

1 

174.7515 

2430.1833 

$ 

191.2419 

2910.5083 

f 

175.1442 

2441.0772 

61 

191.6376 

2922.4734 

7 

¥ 

175.5369 

2452.0310 

i 

192.0303 

2934.4630 

56 

175.9296 

2463.0144 

i 

4 

192.4230 

2946.4771 

i 

176.3323 

2474.0222 

3. 

8 

192.8157 

2958.5139 

i 

176.7150 

2485.3546 

* 

193.2084 

2970.5791 

1 

177.1077 

2496.1116 

h 

8 

193.6011 

2982.6669 

* 

177.5004 

2507.1931 

a 

4 

193.9931 

2994.7792 


177.8931 

2518.2992 

7 

¥ 

194.3865 

3006.9161 

a 

4 

178.2858 

2529.4297 

62 

194.7792 

3019.0776 

7 

¥ 

178.6785 

2543.5849 

i 

195.1719 

3031.2635 

57 

179.0712 

2551.7646 

i 

195.5646 

3043.4740 


179.4639 

2562.9688 

3 

8 

195.9573 

3055.7091 

* 

179.8566 

2574.1975 

1 

5 

196.3500 

3067.9687 


















THE ENGINEER^ HANDY-BOOK, 


TABLE — (Continued) 


CONTAINING THE DIAM., CIRCUMFERENCES, AND AREAS OF CIRCLES. 


Diam. 

ClRCUM. 

Area. 

Diam. 

ClRCUM. 

Area. 

Inch. 



Inch. 



jj. 

8 

196.7427 

3080.2529 

7 

¥ 

213.2361 

3618.3300 

a. 

4 

197.1354 

3092.5615 

68 

213.6288 

3631.6896 

7 

8 

197.5281 

3104.8948 

£ 

214.0215 

3645.0536 

63 

197.9208 

3117.2526 

i. 

4 

214.4142 

3658.4402 

£ 

198.3135 

3129.6349 

3 

¥ 

214.8069 

3671.8554 

£ 

198.7062 

3142.0417 

£ 

215.1996 

3685.2931 

3 

¥ 

199.0989 

3154 4732 

£ 

215.5923 

3698.7554 

£ 

199.4916 

3166.9291 

a 

4 

215.9850 

3712.2421 


199.8843 

3179.4096 

7 

¥ 

216.3777 

3725.7535 

a. 

4 

200.2770 

3191.9146 

69 

216.7704 

3739.2894 

7 

¥ 

200.6697 

3204.4442 

£ 

217.1631 

3752.8498 

64 

201.0624 

3216.9984 

£ 

217.5558 

3766.4327 

£ 

201.4551 

3229.5770 

1 

217.9485 

3780.0443 

£ 

201.8478 

3242.1782 

£ 

218.3412 

3793.6783 

# 

202.2405 

3254.8080 

£ 

218.7339 

3807.3369 

£ 

202.6332 

3267.4603 

a 

4 

219.1266 

3821.0200 

1 

203.0259 

3280.1372 

7 

¥ 

219.5193 

3834.7277 

£ 

203.4186 

3292.8385 

70 

219.9120 

3848.4600 

7 

¥ 

203.8113 

3305.5645 

£ 

220.3047 

3862.2167 

65 

204.2040 

3318.3151 

£ 

220.6974 

3875.9960 

£ 

£ 

204.5917 

3331.0900 

3 

6 

221.0901 

3889.8039 

204.9894 

3343.8875 

£ 

221.4828 

3903.6343 

t 

205.3821 

3356.7137 

£ 

221.8755 

3917.4893 

£ 

205.7748 

3369.5623 

£ 

222.2682 

3931.3687 

1 

206.1675 

3382.4355 

7 

8 

222.6609 

3945.2728 

£ 

206.5602 

3395.3332 

71 

223.0536 

3959.2014 

7 

¥ 

206.9529 

3408.2555 

£ 

223.4463 

3973.1545 

66 

207.3456 

3421.2024 

£ 

223.8390 

3987.1301 

1 

t 

207.7383 

3434.1737 

3 

8 

224.2317 

4001.1344 

£ 

£ 

208.1310 

3447.1676 

£ 

224.6244 

4015.1611 

208.5237 

3468.1901 

£ 

225.0171 

4029.2124 

£ 

208.9164 

3473.2351 

£ 

225.4098 

4043.2882 

£ 

209.3091 

3486.3047 


225.8025 

4057.3886 

4 

209.7018 

3499.3987 

72 

226.1952 

4071.5136 

7 

¥ 

210.0945 

3512.5174 

£ 

226.5879 

4085.6631 

67 

210.4872 

3525.6606 

£ 

226.9806 

4099.8350 

£ 

210.8799 

3538.8283 

227.3733 

4114.0356 

£ 

211.2726 

3552.0185 

£ 

227.7660 

4128.2587 

3 

g 

211.6653 

3565.2374 

£ 

228.1587 

4142.5064 

£ 

212.0580 

3578.4787 

a 

4 

228.5514 

4156.7785 

£ 

212.4507 

3591.7446 

f 

228.9441 

4171.0753 

a 

4 

212.8434 1 

3605.0350 

73 

229.3368 

4185.3966 


551 


















55*2 


THE ENGINEER’S HANDY-BOOK. 


TABLE-( Continued ) 

CONTAINING THE DIAM., CIRCUMFERENCES, AND AREAS OF CIRCLES. 


Diam. 

ClRCUM. 

Area. 

Diam. 

ClRCUM. 

Area. 

Inch. 



Inch. 



£ 

229.7295 

4199.7424 

3 

8 

246.2229 

4824.4299 

£ 

230.1222 

4214.1107 

£ 

246.6156 

4839.8311 

3 

8 

230.5149 

4228.5077 

1 

247.0083 

4855.2568 

£ 

230.9076 

4242.9271 

3 

4 

247.4010 

4870.7071 

* 

231.3003 

4257.3711 

7 

¥ 

247.7937 

4886.1820 

1 

231.6930 

4271.8396 

79 

248.1864 

4901.6814 

£ 

232.0857 

4286.3327 

£ 

248.5791 

4917.2053 

74 

232.4784 

4300.8504 

£ 

248.9718 

4932.7517 

i 

¥ 

232.8711 

4315.3926 

i 

249.3645 

4948.3268 

£ 

233.2638 

4329.9572 

£ 

249.7572 

4963.9243 

1 

233.6565 

4344.5505 


250.1499 

4979.5456 

£ 

234.0492 

4359.1663 

a 

4 

250.5426 

4995.1930 


234.4419 

4373.8067 

7 

¥ 

250.9353 

5010.8642 

4 

234.8346 

4388.4715 

80 

251.3280 

5026.5600 

1 

235.2273 

4403.1610 

£ 

251.7207 

5042.2803 

75 

235.6200 

4417.8750 

£ 

252.1134 

5058.0230 

£ 

236.0127 

4432.6135 

3 

¥ 

252.5061 

5073.7944 

£ 

236.4054 

4447.3745 

£ 

252.8988 

5089.5883 

1 

236.7981 

4462.1642 

5 

253.2915 

5106.4060 

1 

237.1908 

4476.9763 

I ” 

253.6842 

5121.2497 

1 

237.5835 

4491.8130 

¥ 

254.0769 

5137.1173 

a 

4 

237.9762 

4506.6742 

81 

254.4696 

5153.0094 

1 

238.3689 

4521.5600 

¥ 

254.8623 

5168.9260 

76 

238.7616 

4536.4704 

1 

4 

255.2550 

5184.8651 

£ 

239.1543 

4551.4023 

3 

8 

255.6477 

5200.8329 

* 

239.5470 

4566.3626 

£ 

256.0404 

5216.8231 

3 

8 

239.9397 

4581.3486 

1 

256.4331 

5232.8371 

* 

240.3324 

4596.3571 

f 

256.8258 

5248.8772 

| 

240.7251 

4611.3902 

£ 

257.2105 

5264.9411 

a 

4 

241.1178 

4626.4477 

82 

257.6112 

5281.0296 

I 

241.5105 

4641.3299 

i 

g 

258.0039 

5297.1426 

77 

241.9032 

4656.6366 

£ 

258.3966 

5313.2780 

1 

242.2959 

4671.7678 

1 

258.7893 

5329.4421 

£ 

242.6886 

4686.9215 i 

£ 

259.1820 

5345.6287 

3 

¥ 

243.0813 

4702.1039 


259.5747 

5361.8391 

£ 

243.4740 

4717.3087 

a 

4 

259.9674 

5378.0755 


243.8667 

4732.5381 

1 

260.3601 

5394.3358 

a 

4 

244.2594 

4747.7920 

83 

260.7528 

5410.6206 

1 

244.6521 

4763.0705 

1 

8 

261.1455 

5426.9299 

78 

245.0448 

4778.3736 

X 

4 

261.5382 

5443.2617 

£ 

245.4375 

4793.7012 

3 

8 

261.9309 

5459.6222 

£ 

245.8302 

4809.0512 

£ 

262.3236 

5476.0051 
















553 


T PI E ENGINEER’S HANDY-BOOK. 


TABLE- ( Continued ) 


CONTAINING THE DIAM., CIRCUMFERENCES, AND AREAS OF CIRCLES. 


Diam. 

ClRCUM. 

Area. 

Diam. 

ClRCUM. 

Area. 

Inch. 

1 

262.7163 

6492.4118 

Inch. 

i 

279.2097 

6203.6905 

f 

263.1090 

5508.8446 

89 

279.6024 

6221.1534 

7 

F 

263.5017 

5525.3012 

i 

279.9951 

6238.6408 

84 

263.8944 

5541.7824 

* 

280.3878 

6256.1507 

i 

264.2871 

5558.2881 

1 

280.7805 

6273.6893 

* 

264.6798 

5574.8162 

* 

281.1732 

6291.2503 

# 

265.0725 

5591.3730 

t 

281.5659 

6308.8351 


265.4652 

5607.9523 

t 

281.9586 

6326.4460 

I 

265.8579 

5624.5554 

£ 

282.3513 

6344.0807 

I 

266.2506 

5641.1845 

90 

282.7440 

6361.7400 

l 

266.6433 

5657.8357 

1 

283.1367 

6379.4238 

85 

267.0360 

5674.5150 

i 

283.5294 

6397.1300 

i 

267.4287 

5691.2170 

i 

283.9221 

6414.8649 

4 

267.8214 

5707.9415 

* 

284.3148 

6432.6223 

| 

268.2141 

5724.6947 


284.7075 

6450.4039 


268.6068 

5741.4703 

t 

285.1002 

6468.2107 

| 

268.9997 

5758.2697 

1 

285.4929 

6486.0418 

4 

269.3922 

5775.0952 

91 

285.8856 

6503.8974 

1 

269.7849 

5791.9445 

A 

286.2783 

6521.7772 

86 

270.1776 

5808.8184 

| 

286.6710 

6539.6801 


270.5703 

5825.7168 

a 

¥ 

287.0637 

6557.6114 

| 

270.9630 

5842.6376 

* 

287.4564 

6573.5651 

4 

271.3557 

5859.5871 


287.8491 

6593.5431 

4 

271.7484 

5876.5591 


288.2418 

6611.5462 

4 

272.1411 

5893.5549 

| 

288.6345 

6629.5736 


272.5338 

5910.5767 

92 

289.0272 

6647.6258 

4 

272.9265 

5927.6224 

i 

289.4199 

6665.7021 

87 

273.3192 

5944.6926 

i 

289.8125 

6683.8010 

4 

273.7119 

5961.7873 

3 

IT 

290.2053 

6701.9286 

4 

274.1046 

5978.9045 


290.5980 

6720.0787 

| 

274.4973 

5996.0504 


290.9907 

6738.2530 

4 

274.8900 

6013.2187 

291.3834 

6756.4525 

i 

275.2827 

6030.4108 

1 

291.7661 

6774.6763 

4 

275.6754 

6047.6290 

93 

292.1688 

6792.9248 

| 

276.0681 

6064.8710 


292.5615 

6811.1974 

88 

276.4608 

6082.1376 

| 

292.9542 

6829.4927 

4 

276.8535 

6099.4287 

i 

293.3469 

6847.8167 

4 

277.2462 

6116.7422 

i 

293.7396 

6866.1631 

4 

277.6389 

6134.0844 

1 

294.1323 

6884.5338 

4 

278.0316 

6151.4491 


294.5350 

6902.9296 

4 

278.4243 

6169.8376 

| 

294.9177 

6921.3497 

3 

4 

278.8170 

6186.2591 

94 

295.3104 

6939.7946 


47 



















554 


tiie engineer’s handy-book. 


TABLE-( Concluded) 


CONTAINING THE DIAM., CIRCUMFERENCES, AND AREAS OF CIRCLES. 


Diam. 

ClRCUM. 

Area. 

Diam. 

ClRCUM. 

Area. 

Inch. 

i 

295.7031 

6958.2636 

Inch. 

4 

305.1279 

7408.8868 

4 

296.0958 

6976.7552 

4 

305.5206 

7427.9675 

3 

8 

296.4885 

6995.2755 

3 

8 

305.9133 

7447.0769 

4 

296.8812 

7013.8183 

4 

306.3060 

7466.2087. 

1 

297.2739 

7032.3853 

i 

306.6987 

7485.3648 

a 

4 

297.6666 

7050.9775 

a 

4 

4 

307.0914 

7504.5460 

7 

¥ 

298.0593 

7069.5940 

307.4841 

7523.7515 

95 

298.4520 

7088.2352 

98 

307.8768 

7542.9818 

4 

298.8447 

7106.9005 

4 

308.2695 

7562.2362 

4 

299.2374 

7125.5885 

4 

308.6622 

7581.5132 

1 

299.6301 

7144.3052 

3 

¥ 

309.0549 

7600.8189 

4 

300.0228 

7163.0443 

4 

309.4476 

7620.1471 

1 

300.4155 

7181.8077 

1 

309.8403 

7639.4995 

1 

300.8082 

7200.5962 

i 

310.2330 

7658.8771 

4 

301.2009 

7219.4090 

1 

310.6257 

7678.2790 

96 

301.5936 

7238.2466 

99 

311.0184 

7697.7056 

4 

301.9863 

7257.1083 

4 

311.4111 

7717.1563 

4 

302.3790 

7275.9926 

4 

311.8038 

7736.6297 

4 

302.7717 

7294.9056 

3 

8 

312.1965 

7756.1318 

4 

303.1644 

7313.8411 

4 

312.5892 

7775.6563 

t 

303.5571 

7332.8008 

4 

312.9819 

7795.2051 

a. 

4 

303.9498 

7351.7857 

3 

313.3746 

7814.7790 

7 

¥ 

304.3425 

7370.7949 

| 

313.7673 

7834.3772. 

97 

304.7352 

7389.8288 

100 

314.1600 

7854.0000 


Fop circumference of circles larger than those given in th< 
table, multiply the diameter by 3,1416. 

Example. —Diameter 101" x 3,1416 = 317,3016. 

For areas larger than those in the table, multiply the squan 
of the diameter by the decimal .7854. 

Example.— 101 inchesx 101 =10201 x.7854 = 8011,86 sq. in. 















THE ENGINEER’S HANDY-BOOK 


555 


TABLE 

OF LOGARITHMS OF NUMBERS FROM 0 TO 1000.* 


No. 

0 

1 

O 

3 

4 

5 

6 

7 

8 

9 

Prop. 

0 

0 

00000 

30103 

47712 

60206 

69897 

77815 

84510 

90309 

95424 


10 

00000 

00432 

00860 

01283 

01703 

02118 

02530 

02938 

03342 

03742 

415 

11 

04139 

04532 

04921 

05307 

05690 

06069 

06445 

06818 

07188 

07554 

379 

12 

07918 

08278 

08636 

08990 

09342 

09691 

10037 

10380 

10721 

11059 

349 

13 

11394 

11727 

12057 

12385 

12710 

13033 

13353 

13672 

13987 

14301 

323. 

14 

14613 

14921 

15228 

15533 

15836 

16136 

16435 

16731 

17026 

17318 

300 

15 

17609 

17897 

18184 

18469 

18752 

19033 

19312 

19590 

19865 

20139 

281 

16 

20412 

20682 

20951 

21218 

21484 

21748 

22010 

22271 

22530 

22788 

264 

17 

23045 

23299 

23552 

23804 

24054 

24303 

24551 

24797 

25042 

25285 

249 

18 

25527 

25767 

26007 

26245 

26481 

26717 

26951 

27184 

27415 

27646 

236 

19 

27875 

28103 

28330 

28555 

28780 

29003 

29225 

29446 

29666 

29885 

223 

20 

30103 

30319 

30535 

30749 

30963 

31175 

31386 

31597 

31806 

32014 

212 

21 

32222 

32428 

32633 

32838 

33041 

33243 

33445 

33646 

33845 

34044 

202 

22 

34242 

34439 

34635 

34830 

35024 

35218 

35410 

35602 

35793 

35983 

194 

23 

36173 

36361 

36548 

36735 

36921 

37106 

37291 

37474 

37657 

37839 

185 

24 

38021 

38201 

38381 

38560 

38739 

38916 

39093 

39269 

39445 

39619 

177 

25 

39794 

39967 

40140 

40312 

40483 

40654 

40824 

40993 

41162 

41330 

171 

26 

41497 

41664 

41830 

41995 

42160 

42324 

42488 

42651 

42813 

42975 

164 

27 

43436 

43296 

43456 

43616 

43775 

43933 

44090 

44248 

44404 

44560 

158 

28 

44716 

44870 

45024 

45178 

45331 

45484 

45636 

45788 

45939 

46089 

153 

29 

46240 

46389 

46538 

46686 

46834 

46982 

47129 

47275 

47421 

47567 

148 

30 

47712 

47856 

48000 

48144 

48287 

48430 

48572 

48713 

48855 

48995 

143 

31 

49136 

49276 

49415 

49554 

49693 

49831 

49968 

50105 

50242 

50379 

138 

32 

50515 

50650 

50785 

50920 

51054 

51188 

51321 

51454 

51587 

51719 

184 

33 

51851 

51982 

52113 

52244 

52374 

52504 

52633 

52763 

52891 

53020 

130 

34 

53148 

53275 

53102 

53529 

53655 

53781 

53907 

54033 

54157 

54282 

126 

35 

54407 

54530 

54654 

54777 

54900 

55022 

55145 

55266 

55388 

55509 

122 

36 

55630 

55750 

55870 

55990 

56410 

56229 

56348 

56466 

56584 

56702 

119 

37 

56820 

56937 

57054 

57170 

57287 

57403 

57518 

57634 

57749 

57863 

116 

38 

57978 

58002 

58206 

58319 

58433 

58546 

58658 

58771 

58883 

58995 

113 

39 

59106 

59217 

59328 

59439 

59549 

59659 

59769 

59879 

59988 

60097 

110 

40 

60206 

60314 

60422 

60530 

60638 

60745 

60852 

60959 

61066 

61172 

107 

41 

61278 

61384 

61489 

61595 

61700 

61804 

61909 

62013 

62117 

62221 

104 

42 

62325 

62428 

62531 

62634 

62736 

62838 

62941 

63042 

63144 

63245 

102 

43 

63347 

63447 

63548 

63648 

63749 

63848 

63948 

64048 

64147 

64246 

99 

44 

64345 

64443 

64542 

64640 

64738 

64836 

64933 

65030 

65127 

65224 

98 

45 

65321 

65417 

65513 

65609 

65075 

65801 

65896 

65991 

66086 

66181 

96 

46 

66276 

66370 

66464 

66558 

66651 

66745 

66838 

66931 

67024 

67117 

94 

47 

67210 

67302 

67394 

67486 

67577 

67669 

67760 

67851 

67942 

68033 

92 

48 

68124 

68214 

68304 

68394 

68484 

68574 

68663 

68752 

68842 

68930 

90 

49 

69020 

69108 

69196 

69284 

69372 

69460 

69548 

69635 

69722 

69810 

88 

50 

69897 

69983 

70070 

70156 

70243 

70329 

70415 

70500 

70586 

70671 

86 

51 

70757 

70842 

70927 

71011 

71096 

71180 

71265 

71349 

71433 

71516 

84 

52 

71600 

71683 

71767 

71850 

71933 

72015 

72098 

72181 

72263 

72345 

82 

53 

72428 

72509 

72591 

72672 

72754 

72835 

72916 

72997 

73078 

73158 

81 

54 

73239 

73319 

73399 

73480 

73559 

73639 

73719 

73798 

73878 

73957 

80 

55 

74036 

741151 

74193 

74272 

74351 

74429 

74507 

74585 

74663 

74741 

78 


* Each logarithm is supposed to have the decimal sign (•). before it. 

































556 


THE ENGINEER’S HANDY-BOOK. 


TABLE — ( Continued.) 


No. 

0 

1 

2 

3 

4 

5 

6 

7 

8 

9 

Prop. 

56 

74818 

74896 

74973 

75050 

75127 

75204 

75281 

75358 

75434 

75511 

77 

57 

75587 

75663 

75739 

75815 

75891 

75966 

76042 

76117 

76192 

76267 

75 

58 

76342 

76417 

76492 

76566 

76641 

76715 

76789 

76863 

76937 

77011 

74 

59 

77085 

77158 

77232 

77305 

77378 

77451 

77524 

77597 

77670 

77742 

73 

60 

77815 

77887 

77959 

78031 

78103 

78175 

78247 

78318 

78390 

78461 

72 

61 

78533 

78604 

78675 

78746 

78816 

78887 

78958 

79028 

79098 

79169 

71 

62 

79239 

79309 

79379 

79448 

79518 

79588 

79657 

79726 

79796 

79S65 

70 

63 

79934 

80002 

80071 

80140 

80208 

80277 

80345 

80413 1 

80482 

80550 

69 

64 

80618 

80685 

80753 

80821 

80888 

80956 

81023 

81090 

81157 

81224 

68 

65 

81291 

81358 

81424 

81491 

81557 

81624 

81690 

81756 

81822 

81888 

67 

66 

81954 

82020 

82805 

82151 

82216 

82282 

82347 

82412 

82477 

82542 

66 

67 

82607 

82672 

82736 

82801 

82866 

82930 

82994 

83058 

83123 

83187 

65 

68 

83250 

83314 

83378 

83442 

83505 

83569 

83632 

83695 

83758 

83281 

64 

69 

83884 

83947 

84010 

84073 

84136 

84198 

84260 

84323 

84385 

84447 

63 

70 

84509 

84571 

84633 

84695 

84757 

84818 

84880 

84941 

85003 

85064 

62 

71 

85125 

85187 

85248 

85309 

85369 

85430 

85491 

85551 

85612 

85672 

61 

72 

85733 

85793 

85853 

85913 

85973 

86033 

86093 

86153 

86213 

86272 

60 

73 

86332 

86391 

86451 

86510 

86569 

86628 

86687 

86746 

86805 

86864 

59 

74 

86923 

86981 

87040 

87098 

87157 

87215 

87273 

87332 

87390 

87448 

58 

75 

87506 

87564 

87621 

87679 

87737 

87794 

87852 

87909 

87966 

88024 

57 

76 

88081 

88138 

88195 

88252 

88309 

88366 

88422 

88479 

88536 

88592 

56 

77 

88649 

88705 

88761 

88818 

88874 

88930 

88986 

89042 

89098 

89153 

56 

78 

89209 

89265 

89320 

89376 

89431 

89487 

89542 

89597 

89652 

89707 

55 

79 

89762 

89817 

89872 

89927 

89982 

90036 

90091 

90145 

90200 

90254 

54 

80 

90309 

90363 

90417 

90471 

90525 

90579 

90633 

90687 

90741 

90794 

54 

81 

90848 

90902 

90955 

91009 

91062 

91115 

91169 

91222 

91275 

91328 

53 

82 

91381 

91434 

91487 

91540 

91592 

91645 

91698 

91750 

91803 

91855 

53 

83 

9190/ 

91960 

92012 

92064 

92116 

92168 

92220 

92272 

92324 

92376 

52 

84 

92427 

92479 

92531 

92582 

92634 

92685 

92737 

92788 

92839 

92890 

51 

85 

92941 

92993 

93044 

93095 

93146 

93196 

93247 

93298 

93348 

93399 

51 

86 

93449 

93500 

93550 

93601 

93651 

93701 

93751 

93802 

93852 

93902 

50 

87 

93951 

94001 

94051 

94101 

94151 

94200 

94250 

94300 

94349 

94398 

49 

88 

94448 

94497 

94546 

94596 

94645 

94694 

94743 

94792 

94841 

94890 

49 

89 

94939 

94987 

95036 

95085 

95133 

95182 

95230 

95279 

95327 

95376 

48 

90 

95424 

95472 

95520 

95568 

95616 

95664 

95712 

95760 

95808 

95856 

48 

91 

95904 

95951 

95999 

96047 

96094 

96142 

96189 

96236 

96284 

96331 

48 

92 

96378 

96426 

96473 

96520 

96507 

96614 

96661 

96708 

96754 

96801 

47 

93 

96848 

96895 

96941 

96988 

97034 

97081 

97127 

97174 

97220 

97266 

47 

94 

97312 

97359 

97405 

97451 

97497 

97543 

97589 

97635 

97680 

97726 

46 

95 

97772 

97818 

97863 

97909 

97954 

98000 

98045 

98091 

98136 

98181 

46 

96 

98227 

98272 

98317 

98362 

98407 

98452 

98497 

98542 

98587 

98632 

45 

97 

98677 

98721 

98766 

98811 

98855 

98900 

98945 

98989 

99033 

99078 

45 

98 

99122 

99166 

99211 

99255 

99299 

99343 

99387 

99431 

99475 

99519 

44 

99 

99563 

99607 

99657 

99694 

99738 

997S2 

99825 

99869 

99913 

99956 

44 












































































THE ENGINEER’S HANDY-BOOK 


057 


TABLE 

OF HYPERBOLIC LOGARITHMS. 


Num. 

Log. 

Num. 

Log. 

Num. 

Log. 

Num. 

Log. 

1*01 

•0099 

1-43 

•3576 

1-85 

•6151 

2*27 

•8197 

1-02 

•0198 

1-44 

•3646 

1*86 

•6205 

2-28 

•8241 

103 

•0295 

T45 

•3715 

1*87 

•6259 

2*29 

•8285 

ro4 

•0392 

1-46 

•3784 

1*88 

•6312 

230 

•8329 

1-05 

•0487 

1-47 

•3852 

1-89 

•6365 

2-31 

•8372 

1-06 

•0582 

1*48 

•3920 

1-90 

•6418 

2-32 

•8415 

1-07 

•0676 

1-49 

•3987 

1-91 

•6471 

2-33 

•8458 

1-08 

•0769 

1-50 

•4054 

1-92 

•6523 

2-34 

•8501 

1-09 

•0861 

1*51 

•4121 

1-93 

•6575 

235 

•8544 

1-10 

•0953 

1-52 

•4187 

1-94 

•6626 

2-36 

•8586 

1-11 

•1043 

1-53 

•4252 

1*95 

•6678 

2-37 

•8628 

ri2 

•1133 

1-54 

•4317 

1-96 

•6729 

2-38 

•8671 

ri3 

•1222 

1‘55 

•4382 

1-97 

•6780 

2-39 

•8712 

1-14 

•1310 

1*56 

•4456 

1-98 

•6830 

2-40 

•8754 

ri5 

•1397 

1-57 

•4510 

1-99 

•6881 

2-41 

•8796 

1*16 

•1484 

1-58 

•4574 

2-00 

•6931 

242 

•8837 

1*17 

•1570 

1-59 

•4637 

2-01 

•6981 

2-43 

•8878 

1*18 

*1655 

1-60 

•4700 

2*02 

•7030 

2*44 

•8919 

1-19 

•1739 

1-61 

•4762 

2-03 

•7080 

2*45 

*8960 

1-20 

*1823 

1-62 

•4824 

2-04 

•7129 

2-46 

•9001 

1*21 

T962 

1-63 

•4885 

2-05 

•7178 

2-47 

•9042 

1*22 

•1988 

1-64 

•4946 

2-06 

•7227 

2-48 

•9082 

1-23 

•2070 

1-65 

•5007 

2-07 

•7275 

2-49 

•9122 

1-24 

•2151 

1-66 

•5068 

2-08 

•7323 

2*50 

•9162 

1-25 

•2231 

1-67 

•5128 

2-09 

•7371 

2*51 

•9202 

1-26 

•2341 

1-68 

•5187 

2-10 

•7419 

2*52 

•9242 

1-27 

•2390 

1-69 

•5247 

2-11 

•7466 

2*53 

•9282 

1-28 

•2468 

1-70 

•5306 

2-12 

•7514 

2-54 

•9321 

1-29 

•2546 

1-71 

•5364 

2-13 

•7561 

2-55 

•9360 

1-30 

•2623 

1*72 

•5423 

2*14 

•7608 

2-56 

•9400 

1-31 

•2700 

1*73 

•5481 

2*15 

•7654 

2-57 

•9439 

1-32 

•2776 

1-74 

•5538 

2*16 

•7701 

2-58 

•9477 

1*33 

•2851 

1-75 

•5596 

2-17 

•7747 

2-59 

•9516 

1*34 

•2926 

1-76 

•5653 

2-18 

•7793 

2*60 

•9555 

1*35 

•3001 

1-77 

•5709 

2-19 

•7839 

2-61 

•9593 

1-36 

•3074 

1-78 

•5766 

2*20 

•7884 

2-62 

•9631 

1-37 

•3148 

1-79 

•5822 

2-21 

•7929 

2-63 

•9669 

1-38 

•3220 

1-80 

•5877 

2*22 

•7975 

2*64 

•9707 

1-39 

•3293 

1-81 

•5933 

2-23 

•8021 

2-65 

•9745 

1-40 

•3364 

1-82 

•5988 

2-24 

•8064 

2-66 

•9783 

1-41 

•3435 

1-83 

•6043 

2*25 

•8109 

2-67 

•9820 

1*42 

•3506 

1-84 

•6097 

2-26 

•8153 

2-68 

•9858 


47 * 










































558 


THE ENGINEER^ HANDY-BOOK. 


TABLE — ( Continued.) 


’ - 

Num. 

Log. 

Num. 

Log. 

Num. 

Log. 

Num. 

Log. 

2-69 

*9895 

3-11 

1-1346 

3-53 

1-2612 

3-95 

1-3737 

2-70 

•9932 

3-12 

1-1378 

3-54 

1-2641 

3-96 

1-3726 

271 

•9969 

3-13 

1-1410 

3-55 

1-2669 

3-97 

1-3787 

2*72 

1-0006 

3*14 

1*1442 

3-56 

1*2697 

3-98 

1-3812 

2*73 

1-0043 

3-15 

1-1474 

3-57 

1-2725 

3-99 

1-3837 

2*74 

1-0079 

3*16 

1-1505 

3*58 

1-2753 

4-00 

1-3862 

2*75 

1-0116 

3-17 

1-1537 

3*59 

1-2781 

4-01 

1-3887 

2*76 

1-0152 

3-18 

1-1568 

3*60 

1*2809 

4-02 

1-3912 

2*77 

1-0188 

3*19 

1*1600 

3-61 

1-2837 

4-03 

1-3937 

2*78 

1-0224 

3*20 

1-1631 

3-62 

1-2864 

4-04 

1-3962 

2*79 

1-0260 

3-21 

1*1662 

3-63 

1-2892 

4-05 

1-3987 

2*80 

1-0296 

3-22 

1-1693 

3-64 

1-2919 

4-06 

1-4011 

2*81 

1-0331 

3-23 

1*1724 

3-65 

1-2947 

4-07 

1-4036 

2*82 

1-0367 

3*24 

1*1755 

3-66 

1-2974 

4-08 

1-4060 

2*83 

1-0402 

3*25 

1-1786 

3-67 

1*3001 

4-09 

1-4085 

2*84 

1-0438 

3-26 

1-1817 

3*68 

1*3029 

4-10 

1-4109 

2*85 

1-0473 

3-27 

1-1847 

3-69 

1-3056 

4-11 

1-4134 

286 

1-0508 

3-28 

1-1878 

3-70 

1-3083 

4-12 

1-4158 

2*87 

1-0543 

3-29 

1-1908 

371 

1*3110 

4-13 

1-4182 

2*88 

1-0577 

3-30 

1*1939 

3-72 

1-3137 

4T4 

1-4206 

2*89 

1-0612 

3-31 

1-1969 

3*73 

1-3164 

4-15 

1-4231 

2-90 

1-0647 

3-32 

1-1999 

3-74 

1-3190 

4-16 

1-4255 

2*91 

1-0681 

3*33 

1*2029 

3*75 

1-3217 

4-17 

1-4279 

2*92 

1-0715 

3*34 

1-2059 

3-76 

1-3244 

4-18 

1*4303 

2*93 

1-0750 

3-35 

1-2089 

3-77 

1-3271 

4-19 

1*4327 

2*94 

1-0784 

336 

1-2119 

3-78 

1-3297 

4-20 

1-4350 

2*95 

1-0818 

3*37 

1-2149 

3-79 

1-3323 

4-21 

1-4374 

2*96 

1-0851 

3-38 

1-2178 

3-80 

1-3350 

4-22 

1-4398 

2*97 

1-0885 

3-39 

1-2208 

3-81 

1-3376 

4-23 

1-4421 

2-98 

1-0919 

3-40 

1-2237 

3*82 

1-3402 

4-24 

1.4445 

2*99 

1-0952 

3-41 

1-2267 

3-83 

1-3428 

4-25 

1-4469 

3*00 

1-0986 

3-42 

1-2296 

3-84 

1-3454 

4-26 

1-4492 

3*01 

1-1019 

3-43 

1-2325 

3-85 

1-3480 

4-27 

1-4516 

3*02 

1-1052 

3*44 

1-2354 

3-86 

1-3506 

4-28 

1*4539 

3*03 

1-1085 

3-45 

1-2387 

3-87 

1-3532 

4-29 

1*4562 

3-04 

1*1118 

3-46 

1-2412 

3-88 

1-3558 

4-30 

1-4586 

3*05 

1-1151 

3-47 

1-2441 

3-89 

1-3584 

4-31 

1-4609 

3*06 

1-1184 

3-48 

1-2470 

3-90 

1-3609 

4-32 

1-4632 

3*07 

1-1216 

3-49 

1-2499 

3-91 

1-3635 

4-33 

1-4655 

3*08 

1-1249 

3-50 

1-2527 

3-92 

1-3660 

4-34 

1*4678 

3*09 

1-1281 

3-51 

1-2556 

3-93 

1-3686 

4-35 

1-4701 

3T0 

b 

1-1314 

3-52 

1-2584 

3-94 

1-3711 

4-36 

1-4724 

_ 



































559 


THE ENGINEER^ HANDY-BOOK. 


T A BLE — ( Concluded .) 


Num. 

Log. 

Num. 

Log. 

Num. 

Log. 

Num. 

Log. 

4-37 

1-4747 

4-79 

1-5665 

5-21 

1-6505 

5-63 

1-7281 

4*38 

1-4778 

4*80 

1-5686 

5-22 

1-6524 

5-64 

1-7298 

4*39 

1-4793 

4-81 

1-5706 

5-23 

1-6544 

5-65 

1-7316 

4-40 

1-4816 

4-82 

1-5727 

5-24 

1-6563 

5-66 

1-7334 

4-41 

1-4838 

4-83 

1-5748 

5-25 

1-6582 

5-67 

1-7351 

442 

1-4858 

4-84 

1-5769 

5-26 

1-6601 

5-68 

1-7369 

4-43 

1-4883 

4-85 

1-5789 

5-27 

1-6620 

5-69 

1-7387 

4*44 

1-4906 

4-86 

1-5810 

5-28 

1-6639 

5-70 

1-7404 

4’45 

1-4929 

4-87 

1-5830 

5-29 

1-6658 

5*71 

1-7422 

4-46 

1-4954 

4-88 

1-5851 

5-30 

1-6677 

5-72 

1-7439 

4*47 

1-4973 

4-89 

1-5870 

5-31 

1-6695 

5-73 

1-7457 

4-48 

1-4996 

4-90 

1-5892 

5-32 

1-6714 

5-74 

1-7474 

4‘49 

1-5018 

4-91 

1-5912 

5'33 

1-6733 

5-75 

1-7491 

4*50 

1-5040 

4-92 

1-5933 

5-34 

1-6752 

5-76 

1-7509 

4"51 

1-5062 

4-93 

1-5953 

5-35 

1-6770 

5-77 

1-7526 

452 

1-5085 

4-94 

1-5973 

536 

1-67;9 

5-78 

1-7544 

4*53 

1-5107 

4-95 

1-5993 

5-37 

1-6808 

5-79 

1-7561 

4-54 

1-5129 

4-96 

1-6014 

5-38 

1-6826 

5'80 

1-7578 

4-55 

1-5151 

4-97 

1-6034 

5-39 

1-6845 

5-81 

1-7595 

4-56 

1-5173 

4-98 

1-6054 

5-40 

1-6863 

5-82 

1-7613 

4-57 

1-5195 

4-99 

1-6074 

5-41 

1-6882 

5-83 

1-7630 

4-58 

1-5216 

5-00 

1-6094 

5-42 

1-6900 

5-84 

1-7647 

4'59 

1-5238 

5-01 

1-6114 

5-43 

1-6919 

5-85 

1-7664 

4-60 

1-5260 

502 

1-6134 

5*44 

1-6937 

5-86 

1-7681 

4-61 

1-5282 

5-03 

1-6154 

5-45 

1-6956 

5-86 

1-7698 

4-62 

1-5303 

5-04 

1-6174 

5-46 

1-6974 

5*87 

1-7715 

4-63 

1-5325 

5-05 

1-6193 

5-47 

1-6992 

5'88 

1-7732 

4*64 

1-5347 

5-06 

1-6213 

5-48 

1-7011 

5-89 

1-7749 

4-65 

1-5368 

5-07 

1-6233 

5-49 

1-7029 

5-90 

1-7766 

4-66 

1-5390 

5-08 

1-6253 

5-50 

1-7047 

5-91 

1-7783 

4-67 

1-5411 

5-09 

1-6272 

5-51 

1-7065 

5-92 

1-7800 

4-68 

1-5432 

5-10 

1-6292 

5-52 

1-7083 

5-93 

1-7817 

4*69 

1-5454 

5-11 

1-6311 

5-53 

1-7101 

5-94 

1-7833 

470 

1-5475 

5-12 

1-6331 

5"54 

1-7119 

5-95 

1-7850 

4-71 

1-5496 

513 

1-6351 

5-55 

1-7137 

5-96 

1-7867 

472 

1-5518 

5-14 

1-6370 

5-56 

1-7155 

5-97 

1-7884 

473 

1-5539 

5-15 

1-6389 

5-57 

1-7173 

5-99 

1-7900 

474 

1-5560 

5-16 

1-6409 

5-58 

1-7191 

6-00 

1-7917 

475 

1-5581 

5-17 

1-6428 

5*59 

1-7209 

6-01 

1-7934 

4-76 

1-5602 

5-18 

1-6448 

5-60 

1-7227 

6-02 

1-7950 

4*77 

1-5623 

5*19 

1-6463 

5-61 

1-7245 

6-03 

1-7967 

478 

1-5644 

5-20 

1 

1-6486 

5-62 

1-7263 

! 6-04 

1-7989 












































560 


THE ENGINEER^ HANDY-BOOK. 


Peculiarities of Multiplication. 

The multiplication of 987654321 by 45 gives 4444444445. 
Reversing the order of the digits, and multiplying 123456789 
by 45, we get a result equally curious, 5555555505. If we take 
123456789 as the multiplicand, and, interchanging the figures 45, 
take 54 as the multiplier, we obtain another remarkable product, 
6666666606. Returning to the multiplicand first used, 987654321, 
and taking 54 as the multiplier again, we get 53333333334,— all 
threes except the first and last figures, which read together 54, the. 
multiplier. Taking the same multiplicand, and using 27, the 
half of 54, as the multiplier, we get a product of 2666666667,— 
all sixes except the first and last figures, which read together 27, 
the multiplier. Next, interchanging the figures in the number 
27, and using 72 as a multiplier, with 987654321 as the multi¬ 
plicand, we obtain a product of 71111111112,— all ones except 
the first and last figures, which read together gives 72, the mul¬ 
tiplier. 

Decimal Arithmetic. 

Decimal Arithmetic is the most simple and explicit mode of 
performing practical calculations, on account of its doing away 
with the necessity of fractional parts in the fractional form, 
thereby reducing long and tedious operations to a few figures. 

Decimal Fractions are fractions in which the denominator is a 
unit, or 1, with ciphers annexed, in which case they are com¬ 
monly expressed by writing the numerator only with a point be¬ 
fore it, by which it is separated from whole numbers; thus *5, which 
denotes five-tenths, T %; *25, that is, T \ 5 a . Ciphers on the right 
hand of decimals are of no value whatever; but placed on the 
left hand, they diminish the decimal value in a tenfold propor¬ 
tion ; thus ’6 signifies 6 tenths; -06 signifies 6 hundredths; and ’006 
signifies 6 thousandths of the integer or whole number. 


THE ENGINEER’S HANDY-BOOK 


561 


TABLE 

OF VULGAR AND DECIMAL FRACTIONS OF AN INCH. 


Vulgar 
Fractious 
ofan Inch. 

Decimal 
Fractions 
ofan Inch. 

Vulgar 
Fractions 
ofan Inch. 

Decimal 
Fractions 
ofan Inch. 

Vulgar 
Fractions 
ofan Inch. 

Decimal 
Fractions 
ofan Inch. 

i 

3 2 

i 

1 6 

l 1 

16 32 

1 

8 

1 1 

8 32 

3 

1 6 

3 1 

16 32 

1 

4 

1 1 

4 3 2 

5 

76 

5 1 

16 32 

•03125 

•0625 

•09375 

•125 

•15625 

•1875 

•21875 

•25 

•28125 

•3125 

•34375 

3 

8 

3 1 

8 32 

7 

1 6 

_7 1 

16 32 

1 

2 

1 1 

2 32 

9 

1 6 

9 1 . 

16 32 

5 

8 

5 1 

8 32 

•375 

•40625 

•4375 

•46375 

•5 

•53125 

*5625 

•59375 

•625 

•65625 

l l 

T6 

i 1 1 

16 32 

3 

4 

3 1 

4 32 

1 3 

1 6 

1 3 1 

16 32 

7 

T 

7 1 
& 32 

1 5 

1 6 

1 5 1 

16 32 

•6875 

•71875 

•75 

•78125 

•8125 

•84375 

•875 

•90625 

•9375 

•96875 


TABLE. 


Com- 


Com- 


Com- 


Com- 


mon 

Deci- 

mon 

Deci- 

mon 

Deci- 

mon 

Deci- 

Frac- 

mal. 

Frac- 

mal. 

Frac- 

mal. 

Frac- 

mal. 

tion. 


tion. 


tion. 


tion. 


i 

32 

•0312 

9 

3 2 

•2812 

1 7 

32 

•5312 

25 

32 

•7812 

i 

To 

•0625 

_5 

1 6 

•3125 

9 

1 5 

•5625 

±A 

1 6 

•8125 

3 

32 

•0937 

1 1 

3 2 

•3437 

1 9 

3 2 

•5977 

2 7 

3 2 

•8437 

1 

S 

•1250 

A 

8 

•3750 

5 

8 

•6250 

1 

8 

•8750 

5 

3 2 

•1562 

1 3 

3 2 

•4062 

2 1 

3 2 

•6562 

29 

3 2 

•9062 

3 

1 6 

•1875 

J 

1 6 

•4375 

1L 

1 6 

•6875 

1 5 

T6 - 

•9375 

7 

32 

•2187 

1 o 

32 

•4687 

£3 

3 2 

•7187 

3 1 

22 

•9687 

1 

4 

•2500 

i 

•5000 

3 

4 

•7500 

32 

32 

1-000 


2 L 






























































562 


THE ENGINEER’S HANDY-BOOK. 


Units. 

Unit of heat. —The unit of heat varies: the French unit of 
heat, called a “ caloric,” is the amount of heat necessary to raise 
one kilogramme (2‘2046215 pounds) of water one degree Centi¬ 
grade, or from 0° C. to 1° C. In this country and in England 
the amount of heat necessary to raise one pound of water one de¬ 
gree Fahrenheit, or from 32° Fah. to 33° Fall., is taken as the 
unit of heat. 

For calculations involving quantity of heat, thermometrical 
temperatures are of no value without a knowledge of the capac¬ 
ity of heat which any body possesses. The quantity of heat re¬ 
quired to raise various bodies to any given temperature differs 
considerably. Water, as possessing the greatest “ specific ” heat 
of any known substance, has been universally accepted as a 
standard, and the unit for the quantity of heat is that amount 
which will raise 1 pound of water 1° Fah. from a temperature of 
32° Fah. To be strictly accurate, the water should be distilled 
and the lower temperature uniform, in any series of experiments, 
for the amount of heat to raise water 1° varies slightly at differ¬ 
ent temperatures. 

Unit of length .— The unit of length used in this country and 
in England is the yard, the length of which has been determined 
by means of a pendulum vibrating seconds, in the latitude of 
London, in a vacuum and at the level of the sea. The length of 
such a pendulum is to be divided into 3,913,929 parts, and 
3,600,000 of these parts are to constitute a yard. The yard is 
divided into 36 inches, so that the length of the seconds pendu¬ 
lum in London is 39T3929 inches. 

The d ivision of a foot into 12 inches enables various fractional 
parts, such as i, i, ±, f, f, to be made by the use of whole 
numbers, and, in this respect, it is far more convenient than 
having the foot divided into ten parts, which will only give J and 
i in the whole divisions, without the use of decimals or fractions. 
So far as the inch is concerned, it is always divided into several 



563 


THE ENGINEER’S HANDY-BOOK. 

proportions, including tenths, on any good rule, and we use those 
most preferred, so that it possesses all the advantages of the deci¬ 
mal system with others peculiarly its own. 

The French unit of length, called the metre, has been taken as 
being the ten-millionth part of the quadrant of a meridian pass¬ 
ing through Paris; that is to say, the ten-millionth part of the 
distance between the equator and the pole, measured through 
Paris. It is equal to 39*3707898 inches. The metre is divided 
into one thousand millimetres, one hundred centimetres, and ten 
decimetres; while a decimetre is ten metres, a hectometre one 
hundred metres, a kilometre one thousand metres, and a myria- 
metre ten thousand metres. 

One English yard is equal to 0*91438 metre; while one mile is 
equal to 1*60931 kilometres. 

Unit of surface. — For the unit of surface, the square inch, 
foot, and yard adopted in this country and in England are re¬ 
placed in the metric system by the square millimetre, centimetre, 
decimetre, and metre. 

The unit of length squared becomes the unit for surface area, 
and the same length cubed is the unit for capacity. Cubic inches 
are generally used to express volumes of water, while cubic feet 
is a convenient expression for steam. 

Unit of capacity. — The cubic inch, foot, and yard furnish 
measures of capacity ; but irregular measures, such as the pint 
and gallon, are also used in this country and in England. The 
gallon contains ten pounds avoirdupois weight of distilled water 
at62°Fah.; the pint is one-eighth part of a gallon. 

The French unit of capacity is the cubic decimetre or litre, 
equal to 1*7607 English pints, or 0*2200 English gallon; and we 
have cubic inches, decimetres, centimetres, and millimetres. 

Unit of weight. — The unit of weight used in this country and 
in England, viz., the pound, is derived from the standard gallon, 
which contains 277*274 cubic inches; the weight of one-tenth of 
this is the pound avoirdupois, which is divided into 7000 grains. 

The French measures of weight are derived at once from the 


564 the engineer’s handy-book. 

measures of capacity, by taking the weight of cubic millimetres, 
centimetres, decimetres, or metres of water at their maximum 
density, that is, at 4° C. or 39° Fah. 

Unit of time or duration. — The unit of time or duration is the 
same for all civilized countries. The twenty-fourth part of a mean 
solar day is called an hour, which contains sixty minutes, which 
again is divided into sixty seconds. The second is universally 
used as the unit of duration. 

Another unit of time is the period occupied by the earth in 
making one revolution around the sun, in reference to an assumed 
fixed star, which unit is called a sidereal year, and contains 365 
days, 6 hours, 9 minutes, 9*6 seconds mean solar time. 

Unit of velocity. — The units of velocity adopted by different 
scientific writers vary somewhat; the most usual, perhaps, in re¬ 
gard to sound, falling bodies, projectiles, etc., is the velocity of feet 
or metres per second. In the case of light and electricity, miles 
and kilometres per second are employed. 

Unit of work. —In this country and in England, the unit of 
work is usually the foot-pound, viz., the force necessary to raise 
one pound weight one foot above the earth in opposition to the 
force of gravity. A horse-power is equal to 33,000 pounds raised 
to a height of one foot in one minute of time. 

In France the kilogrammetre is the unit of work, and is the force 
necessary to raise one kilogramme to a height of one metre against 
the force of gravity. One kilogrammetre = 7*233 foot-pounds. 
The cheval-pouvoir is nearly equal to the English horse-power, and 
is equivalent to 32,500 pounds raised to a height of one foot in 
one minute of time. The force competent to produce a velocity 
of one metre in one second, in a mass of one gramme, is some¬ 
times adopted as a unit of force. 

Unit of pressure. —The pressure of the atmosphere at the level 
of the ocean, with the barometer at 30 inches, is taken as the unit 
in estimating and comparing pressures and elastic forces. 


THE ENGINEER’S HANDY- BOOK. 


565 


TABLE 


SHOWING ALL THE UNITS OF LENGTH RECOGNIZED IN ENGLAND SINCE 

THE SIXTEENTH CENTURY. 

3 barleycorns.1 inch. 

1*2 inches ...... 1 Surveyor’s foot tenth. 

1*875 foot tenths (2*25 inches) . . 1 nail. 

1*777 nails (4 inches) .... 1 hand. 

(6*1538 inches side of cube of wine gal. of 223 cub. in.) 

(6*5576 “ “ “ “ beer gal. of 282 cub. in.) 

1*98 hands (7*92 inches) . . .1 link. 


1*136 links (9 inches) 
1*333 quarters (12 inches) 


(12*907 inches side of cubic bush, or 2150*42 cub. in.) 


1*875 feet (2*5 quarters) 

1*2 ell Hamburg (3 quarters) 

1*33 ell Flemish (3 feet) 

(38*73 inches side of cubic wine 
1*25 yards (5 quarters) 

1*644 ell English (6 quarters) 


(5*0397 feet side of cubic cord or 128 cubic feet.) 


1 quarter. 
1 foot. 


. 1 ell Hamburg. 

. 1 ell Flemish. 

. 1 yard. 

ton of 58212 cub. in.) 

. 1 ell English. 

. 1 ell French. 


1*333 ell French (6 feet) 

2*75 fathoms (5*5 yards) 

4 rods (22 yards) 

(68*57 yards side of square acre.) 

10 chains .... 

8 furlongs .... 

1*158 statute miles 
2*59 geographical miles (3 statute miles) 
A cubit is two feet. 

A great cubit is eleven feet. 

A palm is three inches. 

A span is ten and seven-eighth inches. 
A pace is three feet. 

A barrel of flour weighs 196 pounds. 
A barrel of pork weighs 200 pounds. 
48 


1 fathom. 

1 rod, pole or perch. 
1 chain. 

1 furlong. 

1 statute mile. 

1 geographical mile. 
1 league. 



566 


THE ENGINEER’S HANDY-BOOK. 


A barrel of powder weighs twenty-five pounds. 

A firkin of butter weighs fifty-six pounds. 

A tub of butter weighs eighty-four pounds. 

Atoms and Molecules. 

The term atom has been exclusively appropriated by the 
chemist, while the mathematician and physicist have preferred to 
adopt the word molecule to signify those ultimate constituents of 
matter upon whose motions and.relations depend the various states 
of all bodies solid, liquid, and gaseous. It is said that atoms are 
attracted to each other by the attraction of cohesion, and repelled 
by the force of repulsion. By the action of both these forces, the 
atoms are kept in a state of rest. The solidity of a solid depends 
upon the fact that each pair of atoms is in this state of equilib¬ 
rium. These atoms are supposed to be of an oblate, spheroidal 
form. 

The word particle is also freely made use of as involving no 
hypothesis, and meaning simply a small part of any body. Mole¬ 
cule has been defined by Maxwell as “the smallest possible portion 
of a particular substance; ” and, again, as “ that small portion of 
the substance which moves as one lump in the motion of agita¬ 
tion.” 

Every substance is now supposed to be composed of an im¬ 
mense number of molecules, which, even in the solid state, are 
never entirely at rest, and in the gaseous are in a state of per¬ 
petual violent commotion, rushing about in straight lines in all i 
directions with inconceivable rapidity. 

The difficulty of proving or disproving the molecular theory 
lies in our inability to determine the size or shape of a molecule 
by any means in our power. The most powerful microscope fails 
utterly to show them, and should some material for lenses be dis¬ 
covered infinitely superior to glass or other material at present in 
use, we should fall far short of appreciating a molecule through 
the vision. 


567 


THE ENGINEER^ HANDY-BOOK. 

.TABLE 

OF SQUARES, CUBES, AND SQUARE AND CUBE ROOTS OF ALL 

NUMBERS FROM 1 TO 620. 


Number. 

Square. 

Cube. 

Square Root. 

Cube Root. 

1 

1 

1 

1 . 

1 . 

2 

4 

8 

1.4142 136 

1.2599 21 

3 

9 

27 

1.7230 508 

1.4422 496 

4 

16 

64 

2. 

1.5874 011 

5 

25 

125 

2.2360 68 

1.7099 759 

6 

36 

216 

2.4494 897 

1.8171 206 

* 7 

49 

343 

2.6457 513 

1.9129 312 

8 

64 

512 

2.8284 271 

2. 

9 

81 

729 

3. 

2.0800 837 

10 

1 00 

1 000 

3.1622 777 

2.1544 347 

11 

1 21 

1 331 

3.3166 248 

2.2239 801 

12 

1 44 

1 728 

3.4641 016 

2.2894 286 

13 

1 69 

2 197 

3.6055 513 

2.3513 347 

14 

1 96 

2 744 

3.7416 574 

2.4101 422 

15 

2 25 

3 375 

3.8729 833 

2.4662 121 

16 

2 56 

4 096 

4. 

2.5198 421 

17 

2 89 

4 913 

4.1231 056 

2.5712 816 

18 

3 24 

5 832 

4.2426 407 

2.6207 414 

19 

3 61 

6 859 

4.3585 989 

2.6684 016 

20 

4 00 

8 000 

4.4721 36 

2.7144 177 

21 

4 41 

9 261 

4.5825 757 

2.7589 243 

22 

4 84 

10 648 

4.6904 158 

2.8020 393 

23 

5 29 

12 167 

4.7958 315 

2.8438 67 

24 

5 76 

13 824 

4.8989 795 

2.8844 991 

25 

6 25 

15 625 

5. 

2.9240 177 

26 

6 76 

17 576 

5.0990 195 

2.9224 96 

27 

7 29 

19 683 

5.1961 524 

3. 

28 

7 84 

21 952 

5.2915 026 

3.0365 889 

29 

8 41 

24 389 

5.3851 648 

3.0723 168 

30 

9 00 

27 000 

5.4772 256 

3.1072 325 

31 

9 61 

29 791 

5.5677 644 

3.1413 806 

32 

10 24 

32 768 

5.6568 542 

3.1748 021 

33 

10 89 

35 937 

5.7445 626 

3.2075 343 

34 

11 56 

39 304 

5.8309 519 

3.2396 118 

35 

12 25 

42 875 

5.9160 798 

3.2710 663 

36 

12 96 

46 656 

6. 

3.3019 272 

37 

13 69 

50 653 

6.0827 625 

3.3322 218 

38 

14 44 

54 872 

6.1644 14 

3.3619 754 

39 

15 21 

59 319 

6.2449 98 

3.3912 114 

40 

16 00 

64 000 

(>.3245 553 

3.4199 519 

41 

16 81 

68 921 

6.4031 242 

3.4482 172 
















TABLE — ( Continued ) 

OF SQUARES, CUBES, AND SQUARE AND CUBE ROOTS, ETC. 


Number. 

Square. 

Cube. 

Square Root. 

Cube Root. 

42 

17 64 

74 088 

6.4807 407 

3.4760 266 

43 

18 49 

79 507 

6.5574 385 

3.5033 981 

44 

19 36 

85 184 

6.6332 496 

3.5303 483 

45 

20 25 

91 125 

6.7082 039 

3.5568 933 

46 

21 16 

97 336 

6.7823 3 

3.5830 479 

47 

22 09 

103 823 

6.8556 546 

3.6088 261 

48 

23 04 

110 592 

6.9282 032 

3.6342 411 

49 

24 01 

117 649 

7. 

3.6593 057* 

50 

25 00 

125 000 

7.0710 678 

3.6840 314 

51 

26 01 

132 651 

7.1414 284 

3.7084 298 

52 

27 04 

140 608 

7.2111 026 

3.7325 111 

53 

28 09 

148 877 

7.2803 099 

3.7562 858 

54 

29 16 

157 464 

7.3484 692 

3.7797 631 

55 

30 25 

166 375 

7.4161 985 

3.8029 525 

56 

31 36 

175 616 

7.4833 148 

3.8258 624 

57 

32 49 

185 193 

7.5498 344 

3.8485 011 

58 

33 64 

195 112 

7.6157 731 

3.8708 766 

59 

34 81 

205 379 

7.6811 457 

3.8929 965 

60 

36 00 

216 000 

7.7459 667 

3.9148 676 

61 

37 21 

226 981 • 

7.8102 497 

3.9364 972 

62 

38 44 

238 328 

7.8740 079 

3 9578 915 

63 

39 69 

250 047 

7.9372 539 

3.9790 571 

64 

40 96 

262 144 

8. 

4. 

65 

42 25 

274 625 

8.0622 577 

4.0207 256 

66 

43 56 

287 496 

8.1240 384 

4.0412 401 

67 

44 89 

300 763 

8.1853 528 

4.0615 48 

68 

46 24 

314 432 

8.2462 113 

4.0816 551 

69 

47 61 

328 509 

8.3066 239 

4.1015 661 

70 

49 00 

343 000 

8.3666 003 

4.1212 853 

71 

50 41 

357 911 

8.4261 498 

4.1408 178 

72 

51 84 

373 248 

8.4852 814 

4.1601 676 

73 

53 29 

389 037 

8.5440 037 

4.1793 39 

74 

54 76 

405 224 

8.6023 253 

4.1983 364 

75 

56 25 

421 875 

8.6602 54 

4.2171 633 

76 

57 76 

438 976 

8.7177 979 

4.2358 236 

77 

59 29 

456 533 

8.7749 644 

4.2543 21 

78 

60 84 

474 552 

8.8317 609 

4.2726 586 

79 

62 41 

493 039 

8.8881 944 

4.2908 404 

80 

64 00 

512 000 

8.9442 719 

4.3088 695 

81 

65 61 

531 441 

9. 

4.3267 487 

82 

67 24 

551 368 

9.0553 851 

4.3444 815 

83 

68 89 

571 787 

9.1104 336 

4.3620 707 















569 


THE ENGINEER’S HANDY-BOOK. 
TABLE-( Continued ) 


OF SQUARES, CUBES, AND SQUARE AND CUBE ROOTS, ETC. 


Number. 

Square. 

Cube. 

Square Root. 

Cube Root. 

84 

70 56 

592 704 

9.1651 514 

4.3795 191 

85 

72 25 

614 125 

9.2195 445 

4.3968 296 

86 

73 96 

636 056 

9.2736 185 

4.4140 049 

87 

75 69 

658 503 

9.3273 791 

4.4310 476 

88 

77 44 

681 472 

9.3808 315 

4.4479 602 

89 

79 21 

704 969 

9.4339 811 

4.4647 451 

90 

81 00 

729 000 

9.4868 33 

4.4814 047 

91 

82 81 

753 571 

9.5393 92 

4.4979 414 

92 

84 64 

778 688 

9.5916 63 

4.5143 574 

93 

86 49 

804 357 

9.6436 508 

4.5306 549 

94 

88 36 

830 584 

9.6953 597 

4.5468 359 

95 

90 25 

857 375 

9.7467 943 

4.5629 026 

96 

92 16 

884 736 

9.7979 59 

4.5788 57 

97 

94 09 

912 673 

9.8488 578 

4.5947 009 

98 

96 04 

941 192 

9.8994 949 

4.6104 363 

99 

98 01 

970 299 

9.9498 744 

4.6260 65 

100 

1 00 00 

1 000 000 

10. 

4.6415 888 

101 

1 02 01 

1 030 301 

10.0498 756 

4.6570 095 

102 

1 04 04 

1 061 208 

10.0995 049 

4.6723 287 

103 

1 06 09 

1 092 727 

10.1488 916 

4.6875 482 

104 

1 08 16 

1 124 864 

10.1980 39 

4.7026 694 

105 

1 10 25 

1 157 625 

10.2469 508 

4.7176 94 

106 

1 12 36 

1 191 016 

10.2956 301 

4.7326 235 

107 

1 14 49 

1 225 043 

10.3440 804 

4.7474 594 

108 

1 16 64 

1 259 712 

10.3923 048 

4.7622 032 

109 

1 18 81 

1 295 029 

10.4403 065 

4.7768 562 

110 

1 21 00 

1 331 000 

10.4880 885 

4.7914 199 

111 

1 23 21 

1 367 631 

10.5356 538 

4.8058 995 

112 

1 25 44 

1 404 928 

10.5830 052 

4.8202 845 

113 

1 27 69 

1 442 897 

10.6301 458 

4.8345 881 

114 

1 29 96 

1 481 544 

10.6770 783 

4.8488 076 

115 

1 32 25 

1 520 875 

10.7238 053 

4.8629 442 

116 

1 34 56 

1 560 896 

10.7703 296 

4.8769 99 

117 

1 36 89 

1 601 613 

10.8166 538 

4.8909 732 

118 

1 39 24 

1 643 032 

10.8627 805 

4.9048 681 

119 

1 41 61 

1 685 159 

10.9087 121 

4.9186 847 

120 

1 44 00 

1 728 000 

10.9544 512 

4.9324 242 

121 

1 46 41 

1 771 561 

11. 

4.9460 874 

122 

1 48 34 

1 815 848 

11.0453 61 

4.9596 757 

123 

1 51 29 

1 860 867 

11.0905 365 

4.9731 898 

124 

1 53 76 

1 906 624 

11.1355 287 

4.9866 31 

125 

1 56 25 

1 953 125 

11.1803 399 

5. 


48 * 













570 


THE ENGINEER’S HANDY-BOOK. 


TABLE — ( Continued) 


OF SQUARES, CUBES, AND SQUARE AND CUBE ROOTS, ETC. 


Number. 

Square. 

Cube. 

Square Root. 

Cube Root. 

126 

1 

58 

76 

2 

000 

376 

11.2249 

722 

5.0132 979 

127 

1 

61 

29 

2 

048 

383 

11.2694 

277 

5.0265 257 

128 

1 

63 

84 

2 

097 

152 

11.3137 

085 

5.0396 842 

129 

1 

66 

41 

2 

146 

689 

11.3578 

167 

5.0527 743 

130 

1 

69 

00 

2 

197 

000 

11.4017 

543 

5.0657 97 

131 

1 

71 

61 

2 

248 

091 

11.4455 

231 

5.0787 531 

132 

1 

74 

24 

2 

299 

968 

11.4891 

253 

5.0916 434 

133 

1 

76 

89 

2 

352 

637 

11.5325 

626 

5.1044 687 

134 

1 

79 

56 

2 

406 

104 

11.5758 

369 

5.1172 299 

135 

1 

82 

25 

2 

460 

375 

11.6189 

5 

5.1299 278 

136 

1 

84 

96 

2 

515 

456 

11.6619 

038 

5.1425,632 

137 

1 

87 

69 

2 

571 

353 

11.7046 

999 

5.1551 367 

138 

1 

90 

44 

2 

628 

072 

11.7473 

401 

5.1676 493 

139 

1 

93 

21 

2 

685 

619 

11.7898 

261 

5.1801 015 

140 

1 

96 

00 

2 

744 

000 

11.8321 

596 

5.1924 941 

141 

1 

98 

81 

2 

803 

221 

11.8743 

421 

5.2048 279 

142 

2 

01 

64 

2 

863 

288 

11.9163 

753 

5.2171 034 

143 

2 

04 

49 

2 

924 

207 

11.9582 

607 

5.2293 215 

144 

2 

07 

36 

2 

985 

984 

12. 


5.2414 828 

145 

2 

10 

25 

3 

048 

625 

12.0415 

946 

5.2535 879 

146 

2 

13 

16 

3 

112 

136 

12.0830 

46 

5.2656 374 

147 

2 

16 

09 

3 

176 

523 

12.1243 

557 

5.2776 321 

148 

2 

19 

04 

3 

241 

792 

12.1655 

251 

5.2895 725 

149 

2 

22 

01 

3 

307 

949 

12.2065 

556 

5.3014 592 

150 

2 

25 

00 

3 

375 

000 

12.2474 

487 

5.3132 928 

151 

2 

28 

01 

3 

442 

951 

12.2882 

057 

5.3250 74 

152 

2 

31 

04 

3 

511 

008 

12.3288 

28 

5.3368 033 

153 

2 

34 

09 

3 

581 

577 

12.3693 

169 

5.3484 812 

154 

2 

37 

16 

3 

652 

264 

12.4096 

736 

5.3601 084 

155 

2 

40 

25 

3 

723 

875 

12.4498 

996 

5.3716 854 

156 

2 

43 

36 

3 

796 

416 

12.4899 

96 

5.3832 126 

157 

2 

46 

49 

3 

869 

893 

12.5299 

641 

5.3946 907 

158 

2 

49 

64 

3 

944 

312 

12.5698 

051 

5.4061 202 

159 

2 

52 

81 

4 

019 

679 

12.6095 

202 

5.4175 015 

160 

2 

56 

00 

4 

096 

000 

12.6491 

106 

5.4288 352 

161 

2 

59 

21 

4 

173 

281 

12.6885 

775 

5.4401 218 

162 

2 

62 

44 

4 

251 

528 

12.7279 

221 

5.4513 618 

163 

2 

65 

69 

4 

330 

747 

12.7671 

453 

5.4625 556 

164 

2 

68 

96 

4 

410 

944 

12.8062 

485 

5.4737 037 

165 

2 

72 

25 

4 

492 

125 

12.8452 

326 

5.4848 066 

166 

2 

75 

56 

4 

574 

296 

12.8840 

987 

5.4958 647 

167 

2 

78 

89 

4 

657 

463 

12.9228 

48 

5.5068 784 












571 


THE ENGINEER’S HANDY-BOOK. 


TABLE—( Continued) 


OF SQUARES, CUBES, AND SQUARE AND CUBE ROOTS, ETC. 


Number. 

Square. 

Cube. 

Square Root. 

Cube Root. 

168 

2 82 24 

4 741 632 

12.9614 814 

5.5178 484 

169 

2 85 61 

4 826 809 

13. 

5.5287 748 

170 

2 89 00 

4 913 000 

13.0384 048 

5.5396 583 

171 

2 92 41 

5 000 211 

13.0766 968 

5.5504 99 L 

172 

2 95 84 

5 088 448 

13.1148 77 

5.5612 978 

173 

2 99 29 

5 177 717 

13.1529 464 

5.5720 546 

174 

3 02 76 

5 268 024 

13.1909 06 

5.5827 702 

175 

3 06 25 

5 359 375 

13.2287 566 

5.5934 447 

176 

3 09 76 

5 451 776 

13.2664 992 

5.6040 787 

177 

3 13 29 

5 545 233 

13.3041 347 

5.6146 724 

178 

3 16 84 

5 639 752 

13.3416 641 

5.6252 263 

179 

3 20 41 

5 735 339 

13.3790 882 

5.6357 408 

180 

3 24 00 

5 832 000 

13.4164 079 

5.6462 162 

181 

3 27 61 

5 929 741 

13.4536 24 

5.6566 528 

182 

3 31 24 

6 028 568 

13.4907 376 

5.6670 511 

183 

3 34 89 

6 128 487 

13.5277 493 

5.6774 114 

184 

3 38 56 

6 229 504 

13.5646 6 

5.6877 34 

185 

3 42 25 

6 331 625 

13.6014 705 

5.6980 192 

186 

3 45 96 

6 434 856 

13.6381 817 

5.7082 675 

187 

3 49 69 

6 539 203 

13.6747 943 

5.7184 791 

188 

3 53 44 

6 644 672 

13.7113 092 

5.7286 543 

189 

3 57 21 

6 751 269 

13.7477 271 

5.7387 936 

190 

3 61 00 

6 859 000 

13.7840 488 

5.7488 971 

191 

3 64 81 

6 967 871 

13.8202 75 

5.7589 652 

192 

3 68 64 

7 077 888 

13.8564 065 

5.7689 982 

193 

3 72 49 

7 189 057 

13.8924 4 

5.7789 966 

194 

3 76 36 

7 301 384 

13.9283 883 

5.7889 604 

195 

3 80 25 

7 414 875 

13.9642 4 

5.7988 9 

196 

3 84 16 

7 529 536 

14. 

5.8087 857 

197 

3 88 09 

7 645 373 

14 0356 688 

5.8186 479 

198 

3 92 04 

7 762 392 

14.0712 473 

5.8284 867 

199 

3 96 01 

7 880 599 

14.1067 36 

5.8382 725 

200 

4 00 00 

8 000 000 

14.1421 356 

5.8480 355 

201 

4 04 01 

8 120 601 

14.1774 469 

5.8577 66 

202 

4 08 04 

8 242 408 

14.2126 7t>4 

5.8674 673 

203 

4 12 09 

8 365 427 

14.2478 068 

5.8771 307 

204 

4 16 16 

8 489 664 

14.2828 569 

5.8867 653 

205 

4 20 25 

8 615 125 

14.3178 211 

5.8963 685 

206 

4 24 36 

8 741 816 

14.3527 001 

5.9059 406 

207 

4 28 49 

8 869 743 

14.3874 946 

5.9154 817 

208 

4 32 64 

8 998 912 

14.4222 051 

5.9249 921 

209 

4 36 81 

9 129 329 

14.4568 323 

5.9344 721 

























572 


THE ENGINEER’S HANDY-BOOK. 


TABLE — ( Continued) 

OP SQUARES, CUBES, AND SQUARE AND CUBE ROOTS, ETC. 


Number. 

Square. 

Cube. 

Square Root. 

Cube Root. 

210 

4 41 00 

9 261 000 

14.4913 767 

5.9439 22 

211 

4 45 21 

9 393 931 

14.5258 39 

5.9533 418 

212 

4 49 44 

9 528 128 

14.5602 198 

5.9627 32 

213 

4 53 69 

9 663 597 

14.5945 195 

5.9720 926 

214 

4 57 96 

9 800 344 

14.6287 388 

5.9814 24 

215 

4 62 25 

9 938 375 

14.6628 783 

5.9907 264 

216 

4 66 56 

10 077 696 

14.6969 385 

6. 

217 

4 70 89 

10 218 313 

14.7309 199 

6.0092 45 

218 

4 75 24 

10 360 232 

14.7648 231 

6.0184 617 

219 

4 79 61 

10 503 459 

14.7986 486 

6.0276 502 

220 

4 84 00 

10 648 000 

14.8323 97 

6.0368 107 

221 

4 88 41 

10 793 861 

14.8660 687 

6.0459 435 

222 

4 92 84 

10 041 048 

14.8996 644 

6.0550 489 

223 

4 97 29 

11 089 567 

14.9331 845 

6.0641 27 

224 

5 01 76 

11 239 424 

14.9666 295 

6.0731 779 

225 

5 06 25 

11 390 625 

15. 

6.0822 02 

226 

5 10 76 

11 543 176 

15.0332 964 

6.0911 994 

227 

5 15 29 

11 697 083 

15.0665 192 

6.1001 702 

228 

5 19 84 

11 852 352 

15.0996 689 

6.1091 147 

229 

5 24 41 

12 008 989 

15.1327 46 

6.1180 332 

230 

5 29 00 

12 167 000 

15.1657 509 

6.1269 257 

231 

5 33 61 

12 326 391 

15.1986 842 

6.1357 924 

232 

5 38 24 

12 487 168 

15.2315 462 

6.1446 337 

233 

5 42 89 

12 649 337 

15.2643 375 

6.1534 495 

234 

5 47 56 

12 812 904 

15.2970 585 

6.1622 401 

235 

5 52 25 

12 977 875 

15.3297 097 

6.1710 058 

236 

5 56 96 

13 144 256 

15.3622 915 

6.1797 466 

237 

5 61 69 

13 312 053 

15.3948 043 

6.1884 628 

238 

5 66 44 

13 481 272 

15.4272 486 

6.1971 544 

239 

5 71 21 

13 651 919 

15.4596 248 

6.2058 218 

240 

5 76 00 

13 824 000 

15.4919 334 

6.2144 65 

241 

5 80 81 

13 997 521 

15.5241 747 

6.2230 843 

242 

5 85 64 

14 172 488 

15.5563 492 

6.2316 797 

243 

5 90 49 

14 348 907 

15.5884 573 

6.2402 515 

244 

5 95 36 

14 526“784 

15.6204 994 

6.2487 998 

245 

6 00 25 

14 706 125 

15.6524 758 

6.2573 248 

246 

6 05 16 

14 886 936 

15.6843 871 

6.2658 266 

247 

6 10 09 

15 069 223 

15.7162 336 

6.2743 054 

248 

6 15 04 

15 252 992 

15.7480 157 

6.2827 613 

249 

6 20 01 

15 438 249 

15.7797 338 

6.2911 946 

250 

6 25 00 

15 625 000 

15.8113 883 

6.2996 053 

251 

6 30 01 

15 813 251 

15.8429 795 

6.3079 935 
























THE ENGINEER^ HANDY-BOOK 


573 


TABLE — ( Continued) 


OF SQUARES, CUBES, AND SQUARE AND CUBE ROOTS, ETC. 


Number. 

Square. 

Cube. 

Square Root. 

Cube Root. 

252 

6 

35 

04 

16 

003 

008 

15.8745 

079 

6.3163 

596 

253 

6 

40 

09 

16 

194 

277 

15.9059 

737 

6.3247 

035 

254 

6 

45 

16 

16 

387 

064 

15.9373 

775 

6.3330 

256 

255 

6 

50 

25 

16 

581 

375 

15.9687 

194 

6.3413 

257 

256 

6 

55 

36 

16 

777 

216 

16. 


6.3496 

042 

257 

6 

60 

49 

16 

974 

593 

16.0312 

195 

6.3578 

611 

258 

6 

65 

64 

17 

173 

512 

16.0623 

784 

6.3660 

968 

259 

6 

70 

81 

17 

373 

979 

16.0934 

769 

6.3743 

111 

260 

6 

76 

00 

17 

576 

000 

16.1245 

155 

6.3825 

043 

261 

6 

81 

21 

17 

779 

581 

16.1554 

944 

6.3906 

765 

262 

6 

86 

44 

17 

984 

728 

16.1864 

141 

6.3988 

279 

263 

6 

91 

69 

18 

191 

447 

16.2172 

747 

6.4069 

585 

264 

6 

96 

96 

18 

399 

744 

16.2480 

768 

6.4150 

687 

265 

7 

02 

25 

18 

609 

625 

16.2788 

206 

6.4231 

583 

266 

7 

07 

56 

18 

821 

096 

16.3095 

064 

6.4312 

276 

267 

7 

12 

89 

19 

034 

163 

16.3401 

346 

6.4392 

767 

268 

7 

18 

24 

19 

248 

832 

16.3707 

055 

6.4473 

057 

269 

7 

23 

61 

19 

465 

109 

16.4012 

195 

6.4553 

148 

270 

7 

29 

00 

19 

683 

000 

16.4316 

767 

6.4633 

041 

271 

7 

34 

41 

19 

902 

511 

16.4620 

776 

6.4712 

736 

272 

7 

39 

84 

20 

123 

648 

16.4924 

225 

6.4792 

236 

273 

7 

45 

29 

20 

346 

417 

16.5227 

116 

6.4871 

541 

274 

7 

50 

76 

20 

570 

824 

16.5529 

454 

6.4950 

653 

275 

7 

56 

25 

20 

796 

875 

16.5831 

24 

6.5029 

572 

276 

7 

61 

76 

21 

024 

576 

16.6132 

477 

6.5108 

3 

277 

7 

67 

29 

21 

253 

933 

16.6433 

17 

6.5186 

839 

278 

7 

72 

84 

21 

484 

952 

16.6783 

32 

6.5265 

189 

279 

7 

78 

41 

21 

717 

639 

16.7032 

931 

6.5343 

351 

280 

7 

84 

00 

21 

952 

000 

16.7332 

005 

6.5421 

326 

281 

7 

89 

61 

22 

188 

041 

16.7630 

546 

6.5499 

116 

282 

7 

95 

24 

22 

425 

768 

16.7928 

556 

6.5576 

722 

283 

8 

00 

89 

22 

665 

187 

16.8226 

038 

6.5654 

144 

284 

8 

06 

56 

22 

906 

304 

16.8522 

995 

6.5731 

385 

285 

8 

12 

25 

23 

149 

125 

16.8819 

43 

6.5808 

443 

286 

8 

17 

96 

23 

393 

656 

16.9115 

345 

6.5885 

323 

287 

8 

23 

69 

23 

639 

903 

16.9410 

743 

6.5962 

023 

288 

8 

29 

44 

23 

887 

872 

16.9705 

627 

6.6038 

545 

289 

8 

35 

21 

24 

137 

569 

17. 


6.6114 

89 

290 

8 

41 

00 

24 

389 

000 

17.0293 

864 

6.6191 

06 

291 

8 

46 

81 

24 

642 

171 

17.0587 

221 

6.6267 

054 

292 

8 

52 

64 

24 

897 

088 

17.0880 

075 

6.6342 

874 

293 

8 

58 

49 

25 

153 

757 

17.1172 

428 

6.6418 

522 














574 


THE ENGINEER’S HANDY-BOOK 


TABLE — ( Continued ) 


OF SQUARES, CUBES, AND SQUARE AND CUBE ROOTS, ETC. 


Number. 

Square. 

Cube. 

Square Root. 

Cube Root. 

294 

8 64 36 

25 412 184 

17.1464 282 

6.6493 998 

295 

8 70 25 

25 672 375 

17.1755 64 

6.6569 302 

296 

8 76 16 

25 934 336 

17.2046 505 

6.6644 437 

297 

8 82 09 

26 198 073 

17.2336 879 

6.6719 403 

293 

8 88 04 

26 463 592 

17.2626 765 

6.6794 2 

299 

8 94 01 

• 26 730 899 

17.2916 165 

6.6868 831 

300 

9 00 00 

27 000 000 

17.3205 081 

6.6943 295 

301 

9 06 01 

27 270 901 

17.3493 516 

6.7017 593 

302 

9 12 04 

27 543 608 

17.3781 472 

6.7091 729 

303 

9 18 09 

27 818 127 

17.4068 952 

6.7165 7 

304 

9 24 16 

28 094 464 

17.4355 958 

6.7239 508 

305 

9 30 25 

28 372 625 

17.4642 492 

6.7313 155 

306 

9 36 36 

28 652 616 

17.4928 557 

6.7386 641 

307 

9 42 49 

28 934 443 

17.5214 155 

6.7459 967 

308 

9 48 64 

29 218 112 

17.5499 288 

6.7533 134 

309 

9 54 81 

29 503 609 

17.5783 958 

6.7606 143 

310 

9 61 00 

29 791 000 

17.6068 169 

6.7678 995 

311 

9 67 21 

30 080 231 

17.6151 921 

6.7751 69 

312 

9 73 44 

30 371 328 

17.6635 217 

6.7824 229 

313 

9 79 69 

30 664 297 

17.6918 06 

6.7896 613 

314 

9 85 96 

SO 959 144 

17.7200 451 

6.7968 844 

315 

9 92 25 

31 255 875 

17.7482 393 

6.8040 921 

316 

9 98 56 

31 554 496 

17.7763 888 

6.8112 847 

317 

10 04 89 

31 855 013 

17.8044 938 

6.8184 62 

318 

10 11 24 

32 157 432 

17.8325 545 

6.8256 242 

319 

10 17 61 

32 461 759 

17.8605 711 

6.8327 714 

320 

10 24 00 

32 768 000 

17.8885 438 

6.8399 037 

321 

10 30 41 

33 076 161 

17.9164 729 

6.8470 213 

322 

10 36 84 

33 386 248 

17.9443 584 

6.8541 24 

323 

10 43 29 

33 698 267 

17.9722 008 

6.8612 12 

324 

10 49 76 

34 012 224 

18. 

6.8682 855 

325 

10 56 25 

34 328 125 

18.0277 564 

6.8753 433 

326 

10 62 76 

34 645 976 

18.0554 701 

6.8823 888 

327 

10 69 29 

34 965 783 

18.0831 413 

6.8894 188 

328 

10 75 84 

35 287 552 

18.1107 703 

6.8964 345 

329 

10 82 41 

35 611 289 

18.1383 571 

6.9034 359 

330 

10 89 00 

35 937 000 

18.1659 021 

6.9104 232 

331 

10 95 61 

36 264 691 

18.1934 054 

6.9173 964 

332 

11 02 24 

36 594 368 

18.2208 672 

6.9243 556 

333 

11 08 89 

36 926 037 

18.2482 876 

6.9313 088 

334 

11 15 56 

37 259 704 

18.2756 669 

6.9382 321 

335 

11 22 25 

37 595 375 

18.3030 052 

6.9451 496 












THE ENGINEER’S HANDY-BOOK. 575 

TABL E — {Continued) 


or SQUARES, CUBES, AND SQUARE AND CUBE ROOTS, ETC. 


Number. 

Square. 

Cube. 

Square Root. 

Cube Root. 

336 

11 28 96 

37 933 056 

18.3303 028 

6.9520 533 

337 

11 35 69 

38 272 753 

18.3575 598 

6.9589 434 

338 

11 42 44 

38 614 472 

18.3847 763 

6.9658 198 

339 

11 49 21 

38 958 219 

18.4119 526 

6.9726 826 

340 

11 56 00 

39 304 000 

18.4390 889 

6.9795 321 

341 

11 62 81 

39 651 821 

18.4661 853 

6.9863 681 

342 

11 69 64 

40 001 688 

18.4932 42 

6.9931 906 

343 

11 76 49 

40 353 607 

18.5202 592 

7. 

344 

11 83 36 

40 707 584 

18.5472 37 

7.0067 962 

345 

11 90 25 

41 063 625 

18.5741 756 

7.0135 791 

346 

11 97 16 

41 421 736 

18.6010 752 

7.0203 49 

347 

12 04 09 

41 781 923 

18.6279 36 

7.0271 058 

348 

12 11 04 

42 144 192 

18.6547 581 

7.0338 497 

349 

12 18 01 

42 508 549 

18.6815 417 

7.0405 806 

350 

12 25 00 

42 875 000 

18.7082 869 

7.0472 987 

351 

12 32 01 

43 243 551 

18.7349 94 

7.0540 041 

352 

12 39 04 

43 614 208 

18.7616 63 

7.0606 967 

353 

12 46 09 

43 986 977 

18.7882 942 

7.0673 767 

354 

12 53 16 

44 361 864 

18.8148 877 

7.0740 44 

355 

12 60 25 

44 738 875 

18.8414 437 

7.0806 988 

356 

12 67 36 

45 118 016 

18.8679 623 

7.0873 411 

357 

12 74 49 

45 499 293 

18.8944 436 

7.0939 709 

358 

12 81 64 

45 882 712 

18.9208 879 

7.1005 885 

359 

12 88 81 

46 268 279 

18.9472 953 

7.1071 937 

360 

12 96 00 

46 656 000 

18.9736 66 

7.1137 866 

361 

13 03 21 

47 045 831 

19. 

7.1203 674 

362 

13 10 44 

47 437 928 

19.0262 976 

7.1269 36 

363 

13 17 69 

47 832 147 

19.0525 589 

7.1334 925 

364 

13 24 96 

48 228 544 

19.0787 84 

7.1400 37 

365 

13 32 25 

48 627 125 

19.1049 732 

7.1465 695 

366 

13 39 56 

49 027 896 

19.1311 265 

7.1530 901 

367 

13 46 89 

49 430 863 

19.1572 441 

7.1595 988 

368 

13 54 24 

49 836 032 

19.1833 261 

7.1660 957 

369 

13 61 61 

50 243 409 

19.2093 727 

7.1725 809 

370 

13 69 00 

50 653 000 

19.2353 841 

7.1790 544 

371 

13 76 41 

51 064 811 

19.2613 603 

7.1855 162 

372 

13 83 84 

51 478 848 

19.2873 015 

7.1919 663 

373 

13 91 29 

51 895 117 

195132 079 

7.1984 05 

374 

13 98 76 

52 313 624 

19.3390 796 

7.2048 322 

375 

14 06 25 

52 734 375 

19.3649 167 

7.2112 479 

376 

14 13 76 

53 157 376 

19.3907 194 

7.2176 522 

377 

14 21 29 

53 582 633 

19.4164 878 

7.2240 45 






















576 


THE ENGINEER’S HANDY-BOOK. 


TABLE- ( Continued) 

OF SQUARES, CUBES, AND SQUARE AND CUBE ROOTS, ETC. 


Number. 

Square. 

Cube. 

Square Root. 

Cube Root.. 

378 

14 28 84 

54 010 152 

19.4422 221 

7.2304 268 

379 

14 36 41 

54 439 939 

19.4679 223 

7.2367 972 

380 

14 44 00 

54 872 000 

19.4935 887 

7.2431 565 

381 

14 51 61 

55 306 341 

19.5192 213 

7.2495 045 

382 

14 59 24 

55 742 968 

19.5448 203 

7.2558 415 

383 

14 66 89 

56 181 887 

19.5703 858 

7.2621 675 

384 

14 74 56 

56 623 104 

19.5959 179 

7.2684 824 

385 

14 82 25 

57 066 625 

19.6214 169 

7.2747 864 

386 

14 89 96 

57 512 456 

19.6468 827 

7.2810 794 

387 

14 97 69 

57 960 603 

19.6723 156 

7.2873 617 

388 

15 05 44 

58 411 072 

19.6977 156 

7.2936 33 

389 

15 13 21 

58 863 869 

19.7230 829 

7.2998 936 

390 

15 21 00 

59 319 000 

19.7484 177 

7.3061 436 

391 

15 28 81 

59 776 471 

19.7737 199 

7.3123 828 

392 

15 36 64 

60 236 288 

19.7989 899 

7.3186 114 

393 

15 44 49 

60 698 457 

19.8242 276 

7.3248 295 

394 

15 52 36 

61 162 984 

19.8494 332 

7.3310 369 

395 

15 60 25 

61 629 875 

19.8746 069 

7.3372 339 

396 

15 68 16 

62 099 136 

19.8997 487 

7.3434 205 

397 

15 76 09 

62 570 773 

19.9248 588 

7.3495 966 

398 

15 84 04 

63 044 792 

19.9499 373 

7.3557 624 

399 

15 92 01 

63 521 199 

19.9749 844 

7.3619 178 

400 

16 00 00 

64 000 000 

20. 

7.3680 63 

401 

16 08 01 

64 481 201 

20.0249 844 

7.3741 979 

402 

16 16 04 

64 964 808 

20.0499 377 

7.3803 227 

403 

16 24 09 

65 450 827 

20.0748 599 

7.3864 373 

404 

16 32 16 

65 939 264 

20.0997 512 

7.3925 418 

405 

16 40 25 

66 430 125 

20.1246 118 

7.3986 363 

406 

16 48 36 

66 923 416 

20.1494 417 

7.4047 206 

407 

16 56 49 

67 419 143 

20.1742 41 

7.4107 95 

408 

16 64 64 

67 917 312 

20.1990 099 

7.4168 595 

409 

16 72 81 

68 417 929 

20.2237 484 

7.4229 142 

410 

16 81 00 

68 921 000 

20.2484 567 

7.4289 589 

411 

16 89 21 

69 426 531 

20.2731 349 

7.4349 938 

412 

16 97 44 

69 934 528 

20.2977 831 

7.4410 189 

413 

17 05 69 

70 444 997 

20.3224 014 

7.4470 342 

414 

17 13 96 

70 957 944 

20.3469 899 

7.4530 399 

415 

17 22 25 

71 473 375 

20.3715 488 

7.4590 359 

416 

17 30 56 

71 991 296 

20.3960 781 

7.4650 223 

417 

17 38 89 

72 511 713 

20.4205 779 

7.4709 991 

418 

17 47 24 

73 034 632 

20.4450 483 

7.4769 664 

419 

17 55 61 

73 560 059 

20.4694 895 

7.4829 242 















577 


THE ENGINEER’S HANDY-BOOK. 
TABLE-( Continued) 

OF SQUARES, CUBES, AND SQUARE AND CUBE ROOTS, ETC. 


Number. 

Square. 

Cube. 

Square Root. 

Cube Root. 

420 

17 64 00 

74 088 000 

20.4939 015 

7.4888 724 

421 

17 72 41 

74 618 461 

20.5182 845 

7.4948 113 

422 

17 80 84 

75 151 448 

20.5426 386 

7.5007 406 

423 

17 89 29 

75 686 967 

20.5669 638 

7.5066 607 

424 

17 97 76 

76 225 024 

20.5912 603 

7.5125 715 

425 

18 06 25 

76 765 625 

20.6155 281 

7.5184 73 

426 

18 14 76 

77 308 776 

20.6397 674 

7.5243 652 

427 

18 23 29 

77 854 483 

20.6639 783 

7.5302 482 

428 

18 31 84 

78 402 752 

20.6881 609 

7.5361 221 

429 

18 40 41 

78 953 589 

20.7123 152 

7.5419 867 

430 

18 49 00 

79 507 000 

20.7364 414 

7.5478 423 

431 

18 57 61 

80 062 991 

20.7605 395 

7.5536 888 

432 

18 66 24 

80 621 568 

20.7846 097 

7.5595 263 

433 

18 74 89 

81 182 737 

20.8086 52 

7.5653 548 

434 

18 83 56 

81 746 504 

20.8326 667 

7.5711 743 

435 

18 92 25 

82 312 875 

20.8566 536 

7.5769 849 

436 

19 00 96 

82 881 856 

20.8806 13 

7.5827 865 

437 

19 09 69 

83 453 453 

20.9045 45 

7.5885 793 

438 

19 18 44 

84 027 672 

20.9284 495 

7.5943 633 

439 

19 27 21 

84 604 519 

20.9523 268 

7.6001 385 

440 

19 36 00 

85 184 000 

20.9761 77 

7.6059 049 

441 

19 44 81 

85 766 121 

21. 

7.6116 626 

442 

19 53 64 

86 350 888 

21.0237 96 

7.6174 116 

443 

19 62 49 

86 938 307 

21.0475 652 

7.6231 519 

444 

19 71 36 

87 528 384 

21.0713 075 

7.6288 837 

445 

19 80 25 

88 121 125 

21.0950 231 

7.6346 067 

446 

19 89 16 

88 716 536 

21.1187 121 

7.6403 213 

447 

19 98 09 

89 314 623 

21.1423 745 

7.6460 272 

448 

20 07 04 

89 915 392 

21.1660 105 

7.6517 247 

449 

20 16 01 

90 518 849 

21.1896 201 

7.6574 138 

450 

20 25 00 

91 125 000 

21.2132 034 

7.6630 943 

451 

20 34 01 

91 733 851 

21.2367 606 

7.6687 665 

452 

20 43 04 

92 345 408 

21.2602 916 

7.6744 303 

453 

20 52 09 

92 959 677 

21.2837 967 

7.6800 857 

454 

20 61 16 

93 576 664 

21.3072 758 

7.6857 328 

455 

20 70 25 

94 196 375 

21.3307 29 

7.6913 717 

456 

20 79 36 

94 818 816 

21.3541 565 

7.6970 023 

457 

20 88 49 

95 443 993 

21.3775 583 

7.7026 246 

458 

20 97 64 

96 071 912 

21.4009 346 

7.7082 388 

459 

21 06 81 

96 702 579 

21.4242 853 

7.7138 448 

460 

21 16 00 

97 336 000 

21.4476 106 

7.7194 426 

461 

21 25 21 

97 972 181 

21.4709 106 

7.7250 325 


2 M 


49 






























TABLE — ( Continued) 


OF SQUARES, CUBES, AND SQUARE AND CUBE ROOTS, ETC. 


Number. 

Square. 

Cube. 

Square Root. 

Cube Root. 

462 

21 34 44 

98 611 128 

21.4941 853 

7.7306 141 

463 

21 43 69 

99 252 847 

21.5174 348 

7.7361 877 

464 

21 52 96 

99 897 344 

21.5406 592 

7.7417 532 

465 

21 62 25 

100 544 625 

21.5638 587 

7.7473 109 

466 

21 71 56 

101 194 696 

21.5870 331 

7.7528 606 

467 

21 80 89 

101 847 563 

21.6101 828 

7.7584 023 

468 

21 90 24 

102 503 232 

21.6333 077 

7.7639 361 

469 

21 99 61 

103 161 709 

21.6564 078 

7.7694 62 

470 

22 09 00 

103 823< 000 

21.6794 834 

7.7749 801 

471 

22 18 41 

104 487 111 

21.7025 344 

7.7804 904 

■ 472 

22 27 84 

105 154 048 

21.7255 61 

7.7859 928 

473 

22 37 29 

105 823 817 

21.7485 632 

7.7914 875 

474 

22 46 76 

106 496 424 

21.7715 411 

7.7969 745 

475 

22 56 25 

107 171 875 

21.7944 947 

7.8024 538 

476 

22 65 76 

107 850. 176 

21.8174 242 

7.8079 254 

477 

22 75 29 

108 531 333 

21.8403 297 

7.8133 892 

478 

22 84 84 

109 215 352 

21.8632 111 

7.8188 456 

479 

22 94 41 

109 902 239 

21.8860 686 

7.8242 942 

480 

23 04 00 

110 592 000 

21.9089 023 

7.8297 353 

481 

23 13 61 

111 284! 641 

21.9317 122 

7.8351 688 

- 482 

23 23 24 

111 980 168 

21.9544 984 

7.8405 949 

483 

23 32 89 

112 678 587 

21.9772 61 

7.8460 134 

484 

23 42 56 

113 379 904 

22. 

7.8514 244 

• 485 

23 52 25 

114 084 125 

22.0227 155 

7.8568 281 

486 

23 61 96 

114 791 256 

22.0454 077 

‘ 7.8622 242 

487 

23 71 69 

115 501. 303 

22.0680 765 

7.8676 13 

488 

23 81 44 

116 214 272 

22.0907 22 

7.8729 944 

489 

23 91 21 

116 930 169 

22.1133 444 

7.8783 684 

>. 490 ‘ 

24 01 00 

117 649 000 

22.1359 436 

7.8837 352 

491 

24 10 81 

118 370 771 

22.1585 198 

7.8890 946 

492 

24 20 64 

119 095 488 

22.1810 73 

7-8944 468 

493 

24 30 49 

119 823 157 

22.2036 033 

7.8997 917 

494 

24 40 36 

120 553 784 

22.2261 108 

7.9051 294 

495 

24 50 25 

121 287 375 

22.2485 955 

7.9104 599 

496 

24 60 16 

122 023 936 

22.2710 575 

7.9157 832 

497* 

24 70 09 

122 763 473 

22.2934 968 

7.9210 994 

498' 

24 80 04 

123 505 992 

22.3159 136 

7.9264 085 

499 

24 90 01 

124 251 499 

22.3383 079 

7.9317 104 

500 

25 00 00 

125 000 000 

22.3606 798 

7.9370 053 

501 

25 10 01 

125 751 501 

22.3830 293 

7.9422 931 

502 

25 20 04 

126 506 008 

22.4053 565 

7.9475 739 

503 

25 30 09 

127 263 527 

22.4276 615 

7.9528 477 














TABLE — ( Continued,) 

OF SQUARES, CUBES, AND SQUARE AND CUBE ROOTS, ETC. 


Number. 

Square. 

Cube. 

Square Root. 

Cube Root. 

504 

25 40 16 

128 024 064 

22.4499 443 

7.9581 144 

505 

25 50 25 

128 787 625 

22.4722 051 

7.9633 743 

500 

25 60 36 

129 554 246 

22.4944 438 

7.9686 271 

507 

25 70 49 

130 323 843 

22.5166 605 

7.9738 731 

508 

25 80 64 

131 096 512 

22.5388 553 

7.9791 122 

509 

25 90 81 

131 872 229 

22.5610 283 

7.9843 444 

510 

26 01 00 

132 651 000 

22.5831 796 

7.9895 697 

511 

26 11 21 

133 432 831 

22.6053 091 

7.9947 883 

512 

26 21 44 

134 217 728 

22.6274 17 

8. 

513 

26 31 09 

135 005 697 

22.6495 033 

8.0052 049 

514 

26 41 96 

135 796 744 

22.6715 681 

8.0104 032 

515 

26 52 25 

136 590 875 

22.6936 114 

8.0155 946 

516 

26 62 56 

137 388 096 

22.7156 334 

8.0207 794 

517 

26 72 89 

138 188 413 

22.7376 340 

8.0259 574 

518 

26 83 24 

138 991 832 

22.7596 134 

8.0311 287 

519 

26 93 61 

139 798 359 

22.7815 715 

8.0362 935 

520 

27 04 00 

140 608 000 

22.8035 085 

8.0414 515 

521 

27 14 41 

141 420 761 

22.8254 244 

8.0466 03 

522 

27 24 84 

142 236 648 

22.8473 193 

8.0517 479 

523 

27 35 29 

143 055 667 

22.8691 933 

8.0568 862 

524 

27 45 76 

143 877 824 

22.8910 463 

8.0620 18 

525 

27 56 25 

144 703 125 

22.9128 785 

8.0671 432 

526 

27 66 76 

145 531576 

22.9346 899 

8.0722 62 

527 

27 77 29 

146 363 183 

22.9564 806 

8.0773 743 

528 

27 87 84 

147 197 952 

22.9782 506 

8.0824 8 

529 

27 98 41 

148 035 889 

23. 

8.0875 794 

530 

28 09 00 

148 877 000 

23.0217 289 

8.0926 723 

531 

28 19 61 

149 721 291 

23.0434 372 

8.0977 589 

532 

28 30 24 

150 568 768 

23.0651 252 

8.1028 39 

533 

28 40 89 

151 419 437 

23.0867 928 

8.1079 128 

534 

28 51 56 

152 273 304 

23.1084 4 

8.1129 803 

535 

28 62 25 

153 130 375 

23.1300 67 

8.1180 414 

536 

28 72 96 

153 990 656 

23.1516 738 

8.1230 962 

537 

28 83 69 

154 854 153 

23.1732 605 

8.1281 447 

538 

28 94 44 

155 720 872 

23.1948 37 

8.1331 87 

539 

29 05 21 

156 590 819 

23.2163 735 

8.1382 23 

540 

29 16 00 

157 464 000 

23.2379 001 

8.1432 529 

541 

29 26 81 

158 340 421 

23.2594 067 

8.1482 765 

542 

29 37 64 

159 220 088 

23.2808 935 

8.1532 939 

543 

29 48 49 

160 103 007 

23.3023 604 

8.1583 051 

544 

29 59 36 

160 989 184 

23.3238 076 

8.1633 102 

545 

29 70 25 

161 878 625 

23.3452 351 

8.1683 092 

















580 


THE ENGINEER’S HANDY-BOOK. 

TABLE — ( Continued ) 


OF SQUARES, CUBES, AND SQUARE AND CUBE ROOTS, ETC. 


Number. 

Square. 

Cube. 

Square Root. 

Cube Root. 

546 

29 81 16 

162 771 336 

23.3666 429 

8.1733 02 

547 

29 92 09 

163 667 323 

23.3880 311 

8.1782 888 

548 

30 03 04 

164 566 592 

23.4093 998 

8.1832 695 

549 

30 14 01 

165 469 149 

23.4307 49 

8.1882 441 

550 

30 25 00 

166 375 000 

23.4520 788 

8.1932 127 

551 

30 36 01 

167 284 151 

23.4733 892 

8.1981 753 

552 

30 47 04 

168 196 608 

23.4946 802 

8.2031 319 

553 

30 58 09 

169 112 377 

23.5159 52 

8.2080 825 

554 

30 69 16 

170 031 464 

23.5372 046 

8.2130 271 

555 

30 80 25 

170 953 875 

23.5584 38 

8.2179 657 

556 

30 91 36 

171 879 616 

23.5796 522 

8.2228 985 

557 

31 02 49 

172 808 693 

23.6008 474 

8.2278 254 

558 

31 13 64 

173 741 112 

23.6220 236 

8.2327 463 

559 

31 24 81 

174 676 879 

23.6431 808 

8.2376 614 

560 

31 36 00 

175 616 000 

23.6643 191 

8.2425 706 

561 

31 47 21 

176 558 481 

23.6854 386 

8.2474 74 

562 

31 58 44 

177 504 328 

23.7065 392 

8.2523 715 

563 

31 69 69 

178 453 547 

23.7276 21 

8.2572 635 

564 

31 80 96 

179 406 144 

23.7486 842 

8.2621 492 

565 

31 92 25 

180 362 125 

23.7697 286 

8.2670 294 

566 

32 03 56 

181 321 496 

23.7907 545 

8.2719 039 

567 

32 14 89 

182 284 263 

23.8117 618 

8.2767 726 

568 

32 26 24 

183 250 432 

23.8327 506 

8.2816 255 

569 

32 37 61 

184 220 009 

23.8537 209 

8.2864 928 

570 

32 49 00 

185 193 000 

23.8746 728 

8.2913 444 

571 

32 60 41 

186 169 411 

23.8956 063 

8.2961 903 

572 

32 71 84 

187 149 248 

23.9165 215 

8.3010 304 

573 

32 83 29 

188 132 517 

23.9374 184 

8.3058 651 

574 

32 94 76 

189 119 224 

23.9582 971 

8.3106 941 

575 

33 06 25 

190 109 375 

23.9791 576 

8.3155 175 

576 

33 17 76 

191 102 976 

24. 

8.3203 353 

577 

33 29 29 

192 100 033 

24.0208 243 

8.3251 475 

578 

33 40 84 

193 100 552 

24.0416 306 

8.3299 542 

579 

33 52 41 

194 104 539 

24.0624 188 

8.3347 553 

580 

33 64 00 

195 112 000 

24.0831 891 

8.3395 509 

581 

33 75 61 

196 122 941 

24.1039 416 

8.3443 41 

582 

33 87 24 

197 137 368 

24.1246 762 

8.3491 256 

583 

33 98 89 

198 155 287 

24.1453 929 

8.3539 047 

584 

34 10 56 

199 176 704 

24.1660 919 

8.3586 784 

585 

34 22 25 

200 201 625 

24.1867 732 

8.3634 466 

586 

34 33 96 

201 230 056 

24.2074 369 

8.3682 095 

587 

34 45 69 

202 262 003 

24.2280 829 

8.3729 668 



















THE ENGINEER’S HANDY-BOOK 


581 


TABLE - ( Concluded ) 


OF SQUARES, CUBES, AND SQUARE AND CUBE ROOTS, ETC. 


Number. 

Square. 

Cube. 

Square Root. 

Cube Root. 

588 

34 57 44 

203 297 472 

24.2487 113 

8.3777 188 

589 

34 69 21 

204 336 469 

24.2693 222 

8.3824 653 

590 

34 81 00 

205 379 000 

24.2899 156 

8.3872 065 

591 

34 92 81 

206 425 071 

24.3104 916 

8.3919 423 

592 

35 04 64 

207 474 688 

24.3310 501 

8.3966 729 

593 

35 16 49 

208 527 857 

24.3515 913 

8.4013 981 

594 

35 28 36 

209 584 584 

24.3721 152 

8.4061 180 

595 

35 40 25 

210 644 875 

24.3926 218 

8.4108 326 

596 

35 52 16 

211 708 736 

24.4131 112 

8.4155 419 

597 

35 64 09 

212 776 173 

24.4335 834 

8.4202 46 

598 

35 76 04 

213 847 192 

24.4540 385 

8.4249 448 

599 

35 88 01 

214 921 799 

24.4744 765 

8.4296 383 

600 

36 00 00 

216 000 000 

24.4948 974 

8.4343 267 

601 

36 12 01 

217 081 801 

24.5153 013 

8.4390 098 

602 

36 24 04 

218 167 208 

24.5356 883 

8.4436 877 

603 

36 36 09 

219 256 227 

24.5560 583 

8.4483 605 

604 

36 48 16 

220 348 864 

24.5764 115 

8.4530 281 

605 

36 60 25 

221 445 125 

24.5967 478 

8.4576 906 

606 

36 72 36 

222 545 016 

24.6170 673 

8.4623 479 

607 

36 84 49 

223 648 543 

24.6373 7 

8.467 

608 

36 96 64 

224 755 712 

24.6576 56 

8.4716 471 

609 

37 08 81 

225 866 529 

24.6779 254 

8.4762 892 

610 

37 21 00 

226 981 000 

24.6981 781 

8.4809 261 

611 

37 33 21 

228 099 131 

24.7184 142 

8.4855 579 

612 

37 45 44 

229 220 928 

24.7386 338 

8.4901 848 

613 

37 57 69 

230 346 397 

24.7588 368 

8.4948 065 

614 

37 69 96 

231 475 544 

24.7790 234 

8.4994 233 

615 

37 82 25 

232 608 375 

24.7991 935 

8.5040 35 

616 

37 94 56 

233 744 896 

24.8193 473 

8.5086 417 

617 

38 06 89 

234 885 113 

24.8394 847 

8.5132 435 

618 

38 19 24 

236 029 032 

24.8596 058 

8.5178 403 

619 

38 31 61 

237 176 659 

24.8797 106 

8.5224 321 

620 

38 44 00 

238 328 000 

24.8997 992 

8.5270 189 


Any number multiplied into itself 3 times is cubed; as, 3x3x3 
= 27, which is the cube of 3. 

The square root of any number is that number which, multi¬ 
plied into itself, will be equal to the given number; as, V 9 = 3 x 3 ; 
hence 3 is the square root of 9. 





















582 


THE ENGINEER'S HANDY-ROOK. 



The Wetherill Corliss Engine. 




















































































































































































THE ENGINEER’S HANDY-BOOK. 


583 


The Wetherill Corliss Engine. 

The cut on opposite page represents the Wetherill Corliss 
Engine. The frame, as in all other engines of the same type, is 
of the girder pattern, faced up at one end to receive the cylinder, 
to which it is attached by means of turned and reamed-through 
bolts. The cylinder is supported by two pairs of legs, one at 
each end, under the exhaust-chests. The legs, instead of resting 
on a brick or stone foundation, as in the case of other Corliss 
engines, rests on a foundation plate, which prevents the possibil¬ 
ity of one end of the engine settling more than the other. The 
main pillow-block bearings are made in four parts, with cheek 
pieces, which admit of easy and accurate adjustment. The shells 
are of brass, lined with Babbitt metal. 

The cut-off is effected by means of a crab-claw; the valve- 
stems are self-packing, and in some cases the valves are closed 
by steam, while in others dash-pots are employed. The cross¬ 
head wrist-pin is made of steel, and is located directly in the 
centre of the shoes. The pistons are self-packing, and require no 
attention or hand adjustment; the governor is of the fly-ball 
pattern. 

The connecting- and piston-rods and crank-shafts are said to 
be made of the best hammered charcoal-iron, and the crank-pins 
of steel. The connecting-rod boxes are made either of gun-metal 
or government brass. The fly-wheels and driving-pulleys are 
turned on the face and sides, and accurately balanced. The 
Wetherill Corliss engines are made throughout of good material, 
accurately fitted, handsomely finished, arid have a reputation 
second to none, in this country, for efficiency, durability, and 
economy. 

They are claimed to possess advantages peculiar to themselves, 
which render them superior, in many respects, to most other en¬ 
gines of the same type; but such claims are more imaginary than 
real, as it would be difficult to point out any feature of superiority 
in them over other Corliss engines. 




584 


THE ENGINEER’S HANDY-BOOK. 


Emergencies. 

If a follower-plate should break at sea, it might be repaired 
with boiler-plate and tap-bolts, providing these materials were on 
board ; if not, the propeller-shaft should be detached, and the ship 
proceed to the nearest port, under sail. 

If the air-pump rod should break, and no extra rod be on 
board the vessel, remove the air-pump bucket and foot-valve, rig 
a temporary exhaust-pipe with lumber, and proceed to the nearest 
port. 

If a cylinder-head should be fractured or split, it might be re¬ 
paired temporarily by wrought-iron bars, canvas, or other packing, 
and tap-bolts. 

If the cut-off valve should break at one end, remove it from 
the other end, and use steam at whole stroke. 

If the condenser should become so much out of order as to 
render it useless, detach the exhaust-pipe from it, and rig a tem¬ 
porary exhaust with such materials as can be found on board. 

If the crank-pin or truss-block should heat excessively, allow a 
stream of water to run on them continually. 

If the foot-valve should be rendered useless, the air-pump will 
work, providing the discharge is in good order. Foot-valves are 
generally made of vulcanized India-rubber. 

If the delivery-pipe should break, burst, or split, it may be re¬ 
paired temporarily with India-rubber or canvas, lumber, and 
ropes. 

If a crank-pin should break, the broken part may be removed 
and replaced by a new one, providing there is an extra pin on 
hand; if not, detach the propeller and proceed under sail. 

If the propeller-shaft should twist off, disconnect the engines 
from it and proceed under sail; but if one or more of the blades 
should break off, proceed the best way you can, as, while any por¬ 
tion of it remains, it is better than none at all. 




THE ENGINEER’S HANDY-BOOK. 


585 


Questions, 

THE ANSWERS TO WHICH WILL BE FOUND IN THE TEXT. 

What is the pressure of the atmosphere at sea-level ? 

Give the estimated height of the atmosphere. 

Give the component parts of atmospheric air. 

State the difference in weight between air, water, and mercury. 

Does the pressure of the atmosphere differ in different locali¬ 
ties? 

Is the pressure of the atmosphere constant in the same lo¬ 
cality ? 

Give the altitude of some of the highest mountains in the 
world. 

Give the names of the highest waterfalls in the world. 

Give the formula for finding the horse-power of wind-storms. 

Give the meaning of the term fuel. 

Give the component parts of various kinds of fuel. 

Give the comparative values of various kinds of wood for the 
purpose of fuel as compared with coal. 

Give the definitions of the terms fire and smoke. 

( 

Define the term heat. 

Give the specific heat of different substances. 

Give the conductive properties of different substances. 

Define the terms combustion and spontaneous combustion. 




586 the engineer’s handy-book. 


Give the component parts of fresh water. 

Is the specific gravity of all waters the same? 

Give the latent heat of water, ice, and steam. 

1 -s./ 

Define the term vapor. 

Give the meaning of the term gases. 

What is meant by the term area? 

Give the rules for finding the diameters, circumferences, and 

areas of circles. 

Give the meaning of the term cipher. 

Give the meaning of the terms atoms and molecules. 

What advantages does decimal arithmetic possess ? 

What are decimal fractions? 

f- . ■ 

Give an explanation of the different recognized units, such as 
those of heat, length, surface, capacity, weight, time, velocity, 
work, and pressure. 

Give the different lengths which have been recoguized in Eng¬ 
land since the sixteenth century. 


tions. 


Give the decimals for the 16th or 32d part of an inch 


Demonstrate the difference between vulgar and decimal f 



THE ENGINEER’S HANDY-BOOK. 


587 


PART EIGHTH. 


Lexicon of Definitions of Central, Mechanical, and Dynami¬ 
cal Forces. 

Acceleration. — Acceleration is the increase of velocity in a 
moving body, caused by the continued action of the motive force. 
When bodies in motion pass through equal spaces in equal time, 
or, in other words, when the velocity of the body is the same dur¬ 
ing the period that the body is in motion, it is termed uniform 
motion, of which we have a familiar instance in the motion of the 
hands of a clock over the face of it; but a more correct illustra¬ 
tion is the revolution of the earth on its axis. In the case of 
a body moving through unequal spaces in equal times, or with a 
varying velocity, if the velocity increase with the duration of the 
motion, it is termed accelerated motion ; but, if it decrease with 
the duration of the motion, it is termed retarded motion. 

Affinity. — Affinity is a term used in chemistry to denote that 
kind of attraction, by which the particles of different bodies 
unite, and form a compound, possessing properties distinct from 
those of any of the substances which compose it. Thus, when an 
acid and alkali combine, a new substance is formed called a salt, 
perfectly different in its chemical properties from either an acid 
or an alkali; and, in consequence of the law of affinity, these 
bodies have a tendency to unite. 

Angle. — If two lines, drawn on a plain surface, are so situated 
that they meet in a point, or would do so, if sufficiently prolonged, 
they form an opening, which is called an angle. One straight 
line, meeting another which is perpendicular to it, makes the 
angle on both sides equal; then these angles are each called a 
right angle, and, in this case, the one line is said to be perpen¬ 
dicular to the other, or, in the language of mechanics, the one 
line is said to be square with the other; and if the one line be 
horizontal, the perpendicular is said to be plumb to it. The arc, 




588 


THE ENGINEER’S HANDY-BOOK. 


which measures a right angle, is the quarter of the whole circum¬ 
ference, or a quadrant, and contains 90 degrees; any angle meas¬ 
ured by an arc less than this is acute (sharp), and if by an arc 
greater than a quadrant, obtuse (blunt). 

Axle. — An axle is a shaft supporting a wheel; the wheel may 
turn on the axle, or be fastened to it, and the axle turn on bear¬ 
ings. Axles are viewed as having certain relations to girders in 
principle. Girders generally have their two ends resting on two 
points of support, and the load is either located at fixed distances 
from the props, or dispersed over the whole surface of the axle; 
the wheels may be considered the props, and the journals the 
loaded parts. It is found that the inclined surface of the wheel- 
tire, given by coning ranges from 1 to 12 to 1 to 20; and, as a 
matter of course, the direct tendency of the wheel under a load is 
to descend that incline, so that every vertical blow, which the 
wheels may receive, is compounded of two forces, viz., the one to 
crush the wheels in the direction of their vertical plane, and the 
other to move the lower parts of the wheels together. It will be 
seen that these two forces have a direct tendency to bend the axle 
somewhere between the wheels. 

Attraction. — The terms attraction, or affinity, and repulsion, in 
the language of modern scientists, are employed merely as the ex¬ 
pression of one of two general facts, either that the masses or parti¬ 
cles of matter have a tendency to approach and unite to, or to recede 
from, one another, under certain circumstances. The term attraction 
is used synonymously with affinity. All bodies have a tendency 
to attract each other, more or less, and it is this power which is 
called attraction. Attraction is mutual; it extends to indefinite 
distances. All bodies, whatever, as well as their component ele¬ 
mentary particles, are endued with it. It is not annihilated, at 
however great a distance we suppose them to be placed from each 
other; neither does it disappear, though they be arranged ever so 
near each other. The nature of this reciprocal attraction, or at 
least the cause which produces it, is altogether unknown to us. 
Whether it be inherent in all matter, or whether it be the conse- 


THE ENGINEER’S HANDY-BOOK. 


589 


quence of some other agent, are questions beyond the reach of 
human understanding; but its existence is nevertheless certain. 

Capillary Attraction. — Capillary attraction is the property in¬ 
herent in narrow tubes and porous substances, such as sponge, 
lamp-wicking, thread, etc., of raising oil, water, or other fluids 
above their natural level. Hence this principle is applied for 
obtaining a continuous supply of lubricating fluids between rub¬ 
bing and revolving surfaces in motion, by means of a siphon con¬ 
structed of wickings, worsted, or some other substance, one end 
of which is immersed in oil, and the other inserted in the tube 
through which the fluid is to be conducted. 

Centre of Gravity. —The forces with which all bodies tend to 
fall to the earth may be considered parallel; hence every body 
may be considered as acted on by a system of parallel forces whose 
resultant may be found, and these forces, in all positions of the 
body, act on the same points in the same vertical direction. There 
is, therefore, in every body a point through which the resultant 
always passes, in whatever position it is placed. This point is 
called the centre of gravity of the body. The centre of gravity 
of a uniform cylinder or prism is in its axis, and at the middle of 
its length ; of a right cone or a pyramid it is also in the axis, but 
at one-fourth of the height from the base. 

Cohesion. —Cohesion is that quality of the particles of a body 
which causes them to adhere to each other, and to resist being 
torn apart. 

Dynamics. —Dynamics is that branch of mechanics which 
treats of forces in motion producing power and work. It compre¬ 
hends the action of all kinds of machinery, manual and animal 
labor, in the transformation of physical work. 

Elastic Fluids. — Elastic fluids are divided into two classes — 
permanent gases and vapors. The gases cannot be converted into 
the liquid state by any known practicable process; whereas the 
vapors are readily reduced to the liquid form by pressure or dim¬ 
inution of temperature. In respect of their mechanical properties, 
there is, however, no essential difference between the two classes. 

50 





590 


THE ENGINEER’S HANDY-BOOK. 


Elastic fluids, in a state of equilibrium, are subject to the action 
of two forces, namely, gravity, and a molecular force acting from 
particle to particle. 

Elasticity. —Elasticity is that quality which enables a body to 
return to its original form, after having been distorted or stretched 
by some external force. The limit of elasticity is the extent to 
which any material may be stretched without receiving a perma¬ 
nent set. 

Energy. — This term has become obsolete in a mechanical point 
of view, and is now only applied to the action of men and animals. 
If an individual man, horse, ox, or other animal performed a cer¬ 
tain amount of work in less time than another would occupy in 
doing the same work, we say that he acted with great energy; but 
when a machine runs fast, or fire burns fast, or the waves roll fast, 
we do not apply the term energy, but simply say that the machine 
runs at a very high speed, or increased its speed; or the fire 
burned fiercely, or that the wind blew, or the waves rolled with 
great violence. 

Force. —Force is the cause of motion or change of motion in 
material bodies. Every change of motion, viz., every change in 
the velocity of a body, must be regarded as the effect of a force. 
On the other hand, rest, or the invariability of the state of motion 
of a body, must not be attributed to the absence of forces, since op¬ 
posite forces destroy each other and produce no effect. The force 
of gravity with which a body falls to the ground, still acts, though 
the body rests; but this action is counteracted by the solidity of 
the material upon which it reposes. Forces that are balanced so 
as to produce rest, are called statical forces or pressures, to dis¬ 
tinguish them from moving, deflecting, accelerating, or retarding 
forces, i. e., such as are producing motion, or a change in the 
direction or velocity of motion. This distinction is wholly arti¬ 
ficial, as the same force may act in any of these modes; it may 
sometimes be a statical and sometimes an accelerating force. 

Force is any action which can be expressed simply by weight, 
and is distinguished by a great variety of terms, such as attraction, 











THE ENGINEER’S HANDY-BOOK. 


591 


repulsion, gravity, pressure, tension, compression, cohesion, adhe¬ 
sion, resistance, inertia, strain, stress, strength, thrust, burden, load, 
squeeze, pull, push, pinch, punch, etc., all of which may be meas¬ 
ured or expressed by weight without regard to motion, time, 
power, or work. 

Focus. —Focus in geometry is that point in the transverse axis 
of a conic section, at which the double ordinate is equal to a per¬ 
imeter, or to a third proportional to the transverse and conjugate 
axis. 

Friction. —Friction is the resistance offered to the motion of a 
body, when pressed upon the surface of another body which does 
not partake of its motion. Under these circumstances, the sur¬ 
faces in contact have a certain tendency to adhere. Not being 
perfectly smooth, the imperceptible asperities which may be sup¬ 
posed to exist on all surfaces, however highly polished, become to 
some extent interlocked, and, in consequence, a certain amount of 
force is requisite to overcome the mutual resistance to motion of 
the two surfaces, and to maintain the sliding motion even when it 
has been produced. By increasing the pressure, the resistance to 
motion is increased also ; and on the other hand, by rendering the 
surfaces smoother by lubrication, its amount is greatly diminished, 
but can never be entirely annulled. 

Friction cannot be strictly called a force, unless that term be 
taken in a negative sense. The tendency of force, in the rigid 
meaning of the word, is to produce motion; whereas the tendency 
of friction is to destroy motion. 

Friction Rollers. — The obstruction which a cylinder meets in 
rolling along a smooth plane, is quite distinct in its character, and 
far inferior in its amount, to that which is produced by the fric¬ 
tion of the same cylinder drawn lengthwise along a plane. For 
example, in the case of wood rolling on wood, the resistance is to 
the pressure, if the cylinder be small, as 16 or 18 to 1000, and if 
the cylinder be large, this may be reduced to 6 to 1000. The 
friction from sliding, in the same cases, would be to the pressure as 
2 to 10 or 8 to 10, according to the nature of the wood. Hence, 







592 


THE ENGINEER’S HANDY-BOOK. 


by causing one body to roll on another, the resistance is dimin¬ 
ished from 12 to 20 times. It is therefore a principle, in the 
composition of machines, that attrition should be avoided as 
much as possible, and rolling motions substituted whenever cir¬ 
cumstances permit. 

Gravity and Gravitation. — These terms are often used synony¬ 
mously, to denote the mutual tendency which all bodies in nature 
have to approach each other. Gravity acts on gases in the same 
manner as on all other material substances ; but the action of the 
molecular forces is altogether different from that which takes place 
among the elementary particles of solids and liquids, as in the 
case of solid bodies, the molecules strongly attract each other 
(hence results their cohesion), and, in the case of liquids, exert a 
feeble or evanescent attraction, so as to be indifferent to internal 
motion; but, in the case of the gases, the molecular forces are 
repulsive, and the molecules, yielding to the action of these forces, 
tend incessantly to recede from each other, and, in fact, do recede, 
until their further separation is prevented by an exterior obstacle. 

Gravity, Specific. — The specific gravity of a body is the ratio 
of its weight to an equal volume of some other body assumed as 
a conventional standard. The standard usually adopted for solids 
and liquids is rain or distilled water at a common temperature. 
In bodies of equal magnitudes, the specific gravities are directly 
as the weights or as their densities. In bodies of the same specific 
gravity the weights will be as the magnitudes. In bodies of equal 
weights, the specific gravities are inversely as the magnitudes. The 
weights of different bodies are to each other in the compound ratio 
of their magnitudes and specific gravities. Hence, it is obvious 
that, speaking of the magnitude, weight, and specific gravity of 
a body, if any two of them are given, the third may be found. 
A body, immersed in a fluid, will sink if its specific gravity be 
greater than that of the fluid; if it be less, the body will rise to 
the top, and be only partly immersed ; and, if the specific gravity 
of the body and fluid be equal, it will remain at rest in any part 
of the fluid in which it may be placed. When a body is heavier 


THE ENGINEER’S HANDY-BOOK. 


593 


than a fluid, it loses as much of its weight when immersed as is 
equal to a quantity of the fluid of the same bulk or magnitude. 
If the specific gravity of the fluid be greater than that of the 
body, then the quantity of fluid displaced by the part immersed 
is equal to the weight of the whole body. And hence, as the 
specific gravity of the fluid is to that of the body, so is the 
whole magnitude of the body to the part immersed. The spe¬ 
cific gravities of equal solids are as their parts immersed in the 
same fluid. 

Gyration, the Centre of. — The centre of gyration is that point 
in which, if all the matter contained in a revolving system were 
collected, the same angular velocity will be generated in the same 
time by a given force acting at any place, as would be generated 
by the same force acting similarly in the body or system itself. 
The distance of the centre of gyration from the point of suspen¬ 
sion or the axis of motion, is a mean proportional between the 
distances of the centres of oscillation and gravity from the same 
point or axle. 

Horse-power, or Power of a Horse. — The power of a horse 
when applied to draw loads, as well as when made the standard 
of comparison for determining the value of other powers, has 
been variously stated. The relative strength of men and horses 
depends, of course, upon the manner in which their strength is 
applied. Thus, the worst way of applying the strength of a horse 
is to make him carry a weight up a steep hill. The power of a 
horse varies from five to eleven times that of a man. 

Hydrodynamics. — Hydrodynamics is that branch of general 
mechanics which treats of the equilibrium and motion of fluids. 
The terms hydrostatics and hydrodynamics have a signification 
corresponding to the terms statics and dynamics in the mechanics 
of solid bodies, viz., hydrostatics is that division of the science 
which treats of the equilibrium of fluids, and hydrodynamics that 
which relates to their forces and motion. It is, however, usual to 
include the whole doctrine of the mechanics of fluids under the 
general term of hydrodynamics, and to denote the divisions rela- 
50* 2 N 






594 


THE ENGINEER^ HANDY-BOOK. 


tive to their equilibrium and motion by the terms hydrostatics 
and hydraulics. 

Hyperbola. — A plane figure, formed by cutting a section from 
a cone by a plane parallel to its axis, or to any plane within the 
cone, which passes through the cone’s vertex. The curve of the 
hyperbola is such, that the difference, between the distances of 
any point in it from two given points, is always equal to a given 
right line. If the vertices of two cones meet each other, so that 
their axes form one continuous straight line, and the plane of the 
hyperbola cut from one of the cones be continued, it will cut the 
other cone, and form what is called the opposite hyperbola, equal 
and similar to the former; and the distance, between the vertices 
of the two hyperbolae, is called the major axis, or transverse di¬ 
ameter. If the distance between a certain point within the hyper¬ 
bola, called the focus, and any point in the curve be subtracted 
from the distance of said point in the curve from the focus of the 
opposite hyperbola, the remainder will always be equal to a given 
quantity, that is, to the major axis; and the distance of either focus 
from the centre of the major axis is called the eccentricity. The 
line passing through the centre, perpendicular to the major axis, 
and having the distance of its extremities from those of the axis 
equal to the eccentricity, is called the minor axis, or conjugate 
diameter. An ordinate to the major axis, a double ordinate, and 
an absciss mean the same as the corresponding lines in the pa¬ 
rabola. 

Impact is the single instantaneous blow or stroke communi¬ 
cated from one body in motion to another either in motion or at 
rest. 

Impenetrability. — In physics, one of the essential properties of 
matter or body. It is a property inferred from invariable experi¬ 
ence, and resting on this incontrovertible fact, that no two bodies 
can occupy the same portion of space in the same instant of time. 
Impenetrability, as respects solid bodies, requires no proof: it is 
obvious to the touch. With regard to liquids, the property may 
be proved by very simple experiments. Let a vessel be filled to 


THE ENGINEER’S HANDY-BOOK. 


595 


the brim with water, and a solid, incapable of solution in water, 
be plunged into it; a portion of the water will overflow, exactly 
equal in bulk to the dimensions of the body immersed. If a cork 
be rammed hard into the neck of a vial full of water, the vial will 
burst, while its neck remains entire. The disposition of air to re¬ 
sist penetration may be illustrated in the following way: Let a 
tall glass vessel be nearly filled with water, on the surface of 
which a lighted taper is set to float; if, over this glass, a smaller 
cylindrical vessel, likewise of glass, be inverted and pressed down¬ 
wards, the contained air maintaining its place, the internal body 
of the water will descend, while the rest will rise up at the sides, 
and the taper will continue to burn for some seconds encompassed 
by the whole mass of liquid. 

Impetus. — Impetus is the product of the mass and velocity of 
a moving body, considered as instantaneous, as distinguished from 
momentum, with reference to time, and from force, with reference 
to capacity of continuing its motion. Impetus in gunnery is the 
altitude through which a heavy body must fall to acquire a ve¬ 
locity equal to that with which the ball is discharged from the 
piece. 

Incidence. — The term incidence in mechanics is used to denote 
the direction in which a body or ray of light strikes another 
body, and is otherwise called inclination. In moving bodies, their 
incidence is said to be perpendicular or oblique, according as their 
lines of motion make a straight line or an angle at the point of 
contact. 

Inclination. — Inclination denotes the mutual approach or ten¬ 
dency of two bodies, lines, or planes towards each other, so that 
the lines of their direction make at the point of contact an angle 
of greater or less magnitude. 

The Inclined Plane. — The inclined plane is the representative 
of the second class of mechanical powers. Its fundamental law 
of action is that of the composition and resolution of forces. The 
manner in which the advantage is immediately derived from it, is 
therefore distinct from that of the first class; there is necessarily 


596 


THE ENGINEER'S HANDY-BOOK. 


a fulcrum, a point round which all the motion takes place, and 
through which the power acts on the resistance; whereas, in this 
class, there is no apparent centre of action. The advantage gained 
by the inclined plane, when the power acts in a parallel direction 
to the plane, is as the length to the height or angle of inclina¬ 
tion. Hence, divide the weight by the ratio of inclination, and 
the quotient equals the power that will support that weight upon 
the plane. Or, multiply the weight by the height of the plane 
and divide by the length ; the quotient is the power. 

The descent of a body down an inclined plane is as the length 
of the plane to its height; so is the velocity acquired by a fall¬ 
ing body through a given height to the velocity on an inclined 
plane. 

Ex. — A body will roll down an inclined plane 300 feet long 
and 25 feet high in one second of - time, as follows: 300 : 25 : : 16 : 
1*33 = the distance which the body descends per second on an in- 
inclined plane. 

Inertia. — Inertia is that property of matter by which it tends, 
when at rest, to remain so, and, when in motion, to continue in 
motion. 

Levers. — Levers are classified into three different kinds or 
orders. When the fulcrum is between the force and the weight, 
the lever is called a lever of the first order; when the weight is 
between the force and the fulcrum, the lever is of the second 
order; when the force is between the weight and the fulcrum, the 
lever is of the third order. The levers of safety-valves for steam- 
boilers belong to this last class. 

The lever is an inflexible bar, by the application of which one 
force may balance or overcome another. These forces are termed, 
respectively, the power and the resistance or weight, not from any 
difference in the action of the forces, but with reference merely to 
the intention with which the machine is used ; and, indeed, the 
same terms are used about all the other mechanical elements. In 
applying the rod to operate upon any resistance, it must rest upon 
a centre prop, or fulcrum, somewhere along its length, upon which 


THE ENGINEER’S HANDY-BOOK. 597 

»7 

it turns in the performance of its work. Thus, there are three 
points in every lever to be regarded in examining its action, 
namely, the two points of application of the power, the weight, and 
the point resting on the fulcrum. There is a certain relation to 
be observed . between the magnitudes of the opposing force and 
the distances from the fulcrum, namely, that in every case the 
power multiplied by its distance from the fulcrum is equal to the 
weight multiplied by its distance from the same point. From this 
relation, simple rules may be deduced for calculation. 

To know the power to be applied, at a certain distance from 
the fulcrum, to overcome a resistance acting also at a certain dis¬ 
tance, multiply the resistance by its distance from the fulcrum, 
which gives its momentum, and divide the product by the distance 
given ; the quotient will be the power, it being understood that the 
distance and the force be each expressed in the same unit of meas¬ 
ure. For example, a weight, 1120 lbs., at 3 inches from the ful¬ 
crum, is to be balanced by a force at the distance of 10 feet. Now, 
10 feet are equal to 120 inches; and the momentum of 1120 lbs. 
is 1120 X 3 = 3360. Divide this by 120, we have 28 lbs. for the 
power required. Again, To know the distance at which a given 
force ought to be applied to balance a given weight at a certain 
distance, w 7 e must, in like manner, multiply the weight by its dis¬ 
tance, as before, and divide by the given power. 1120 lbs., for ex¬ 
ample, at 3 inches distance, are to be balanced by a force of 28 
lbs. To find the distance of this weight, 1120 lbs. multiplied by 
3 gives 3360, which, divided by 28, gives 120 inches, or 10 feet. 

Machines. — Machines are instruments employed to regulate 
motion, so as to save either time or force. The maximum effect 
of machines is the greatest effect which can be produced by them. 
In all machines that w 7 ork with a uniform motion, there is a cer¬ 
tain velocity, and a certain load of resistance, that yields the 
greatest effect, and which are therefore more advantageous than 
any other. A machine may be so heavily charged, that the mo¬ 
tion, resulting from the application of any given power, will be 
but just sufficient to overcome it, and, if any motion ensue, it 


598 


THE ENGINEER’S HANDY-BOOK. 


will be very trifling, and the whole effect will be very slight. If 
the machine is very lightly loaded, it may give great velocity to 
the load; but, from the smallness of its quantity, the effect may 
still be very inconsiderable; consequently, between these two 
loads, there must be some intermediate one that will render the 
effect the greatest possible. This is equally true in the applica¬ 
tion of animal strength, as in machines. The maximum effect of 
a machine is produced when the weight or resistance to be over¬ 
come is four-ninths of that which the power, when fully exerted, 
is able to balance, or of that resistance which is necessary to re¬ 
duce the machine to rest; and the velocity of the part of the 
. machine, to which the power is applied, should be one-third of 
the greatest velocity of the power. 

The moving power and the resistance being both given, if the 
machine be so constructed, that the velocity of the point, to which 
the power is applied, be to the velocity of the point to which the 
resistance is applied, as four times the resistance to nine times the 
power, the machine will work to the greatest possible advantage. 
This is equally true when applied to the strength of animals; 
that is, a man, horse, or other animal, will do the greatest quantity 
of work, by continued labor, when his strength is opposed to a 
resistance equal to four-ninths of his natural strength, and his 
velocity equal to one-third of his greatest velocity when not im¬ 
peded. In all machines, simple as well as compound, what is 
gained in power is lost in time; but the loss of time is compen¬ 
sated by convenience. The power of a machine is not altered by 
varying the size of the wheels, provided the proportion, produced 
by the multiplication of the power of the several parts, remains 
the same. 

Mechanics. — Mechanics is that branch of natural philosophy 
which treats of three simple physical elements, force, motion, and 
time, with their combinations, constituting power, space, and 
work. Mechanics, regarded as a science, comprehends the sum 
of our knowledge relative to the sensible motions of bodies either 
actually existing, or expressed by the opposition of forces tend- 


THE ENGINEER^ HANDY-BOOK. 


599 


ing to produce motion. The science is thus resolvable into a code 
of discovered laws, applying to the causes which occasion and 
modify the direction and the velocities of motion, and is there¬ 
fore distinct from those branches of science, in which, although 
presenting phenomena of motion in sensible portions of matter, 
we do not consider the circumstances and laws of these motions, 
but only the effects produced. 

When motion itself is considered, the reasoning belongs to 
mechanics, and it is probable that, as our knowledge of the laws 
which govern the phenomena that are evolved under the hand of 
the experimental philosopher becomes more extended, a wider 
meaning will be given to the science of motion. The definition 
which is here given of mechanics is not coeval with the name. 
The science, like most other sciences, has gradually expanded to 
its present extent. It was originally the science of machines — 
these being the first subjects of its speculation ; and, as every 
material combination employed for producing or preventing mo¬ 
tion may be regarded as a machine, and may be resolved into the 
same elementary principles as those employed in machines,— the 
mechanical powers,— the name “ mechanics ” came to be applied 
to motion, and the tendency to motion of any bodies whatever. 
Mechanics still continues to be defined by some the “science of 
force,” and there does not appear to be any valid objection to the 
definition. Force is the cause of motion, and its laws are identi¬ 
cal witli the laws of motion ; and, consequently, the science of 
force coincides, in all its parts, with the science of motion, which 
is mechanics. 

All machinery, when analyzed, will be found to consist of a 
combination of six simple machines or elements, commonly called 
mechanical powers. The six elements are respectively the lever y 
the pulley , the wheel and axle , the inclined plane , the wedge and 
the screw. Though they are not powers, or, in other words, 
sources of power or force, yet they transmit and diffuse or 
concentrate forces. The essential idea of machinery is, that it 
renders force available for effecting practical ends. Machines 


600 


THE ENGINEER^ HANDY-BOOK. 


prepare, as it were, the raw material of force supplied to us frona 
natural sources. It is transmitted and modified by certain com¬ 
binations of the elements of machinery, and is given off, at last, 
in a condition suitable for producing the desired mechanical ef¬ 
fect. We do not create force; the object of machinery is to 
transmit it, and diffuse or concentrate it in one or more points 
of action. The various diffused or concentrated forces, then, 
being added together, will amount exactly to the original avail¬ 
able force. 

Modulus. — The modulus of the elasticity of any substance is a 
column of the same substance, capable of producing a pressure on 
its base, which is to the weight causing a certain degree of com¬ 
pression, as the length of the substance is to the diminution in its 
length. 

Momentum. — Momentum, in mechanics, is the same as impetus 
or quantity of motion, and is generally estimated by the product 
of the velocity and the mass of the body. This is a subject which 
has led to various controversies between philosophers,— some esti¬ 
mating it by the mass into the velocity as stated above, while 
others maintain that it varies as the mass into the square of the 
velocity. But this difference seems to have arisen rather from a 
misconception of the term than from any other cause. Those 
who maintain the former doctrine, understand momentum to sig¬ 
nify the momentary impact; and the advocates of the latter doc¬ 
trine recognize it as the sum of all the impulses till the motion 
of the body is destroyed. 

The momentum of a body is the power contained in a moving 
body, and is equal to its weight multiplied by its velocity. 

The momentum divided by the velocity equals the weight, or 
the momentum divided by the weight equals the velocity. 

The velocity acquired by a falling body is proportional to the 
time; or the velocity acquired at the end of the first second, mul¬ 
tiplied by the number of seconds, will be the velocity with which 
it strikes the ground. 

The space through which a body falls in a given time may be 


THE ENGINEER’S HANDY-BOOK. 


601 


found by multiplying the square of seconds by the distance which 
a body moves in one second from a state of rest, which is 16^ feet, 
or 193 inches, and the product will be the whole space through 
which a body falls in a certain time; if multiplied in feet, the 
product will be feet, and if in inches, the product will be inches. 

The space through which a body falls in any number of sec¬ 
onds may be calculated as follows: During the first second, a body 
falls 16j^ feet; the second second, it will fall 3 times 16^ feet; 
and the third second, 5 times 16f 2 feet. 

The distance passed over by a body in an air-tight vessel by 
the force of gravity is 16 ^ ft.; it gradually acquires an acceler¬ 
ated motion, so that it has a velocity of 32^ ft. at the end of the 
first second. 

Ex. — If a substance weighing 336 pounds be dropped from a 
height of 400 feet, its momentum, and the time it takes to reach 
the ground, may be calculated as follows: 

16 : 1 : : x/400 = 5 seconds, the time of falling. 

Now, to get the momentum, we must have the velocity to mul¬ 
tiply into the weight, and 5 seconds being the time it was falling, 
1 : 32 :: 5 : 160 — velocity in feet x 336 (weight) = 53,760 pounds 
momentum. 

Ex. — If a ball 24 pounds in weight be dropped from a height 
of 400 feet, the velocity with which it will strike the ground, 
and its momentum, may be thus calculated. The time of falling 
must be first found. Then, 16 : 1 : : \/400 — -s/25 = 5 seconds 
is the time of falling. Since the velocity is proportional to the 
time, 1 : 5 : : 32 : 160, which is the velocity in feet with which it 
strikes the ground. Then, as the momentum is equal to the ve¬ 
locity multiplied by the weight, we have 24 x 160 = 3840, the 
momentum. 

Motion. — Motion, in mechanics, is a change of place, or it is 
that property inherent in matter by which it passes from one 
point of space to another. Absolute motion is the absolute 
change of place in a moving body, independent of any other 
motion whatever; in which general sense, however, it never falls 
51 


602 


THE ENGINEER’S HANDY-BOOK. 

under our observation. All those motions, which we consider as 
absolute, are in fact only relative, being referred to the earth, 
which is itself in motion. By absolute motion, therefore, we 
must only understand that which is so with regard to some fixed 
point upon the earth, this being the sense in which it is interpreted 
by writers on this subject. Accelerated motion is that which is 
continually receiving constant accessions of velocity. Angular 
motion is the motion of a body as referred to a centre, about 
which it revolves. Compound motion is that which is produced 
by two or more powers acting in different directions. Natural 
motion is that which is natural to bodies, or that which arises 
from the action of gravity. Parallel Motions.— Contrivances 
of this kind are required for the conversion of rotary and alter¬ 
nating angular motion into rectilineal motion, and the converse; 
but the absolute necessity there is of guiding the path of a piston 
in a steam-engine, has called forth more attention to the principles 
and mechanism of parallel motions than would otherwise, in all 
probability, have been awarded to the subject. Relative motion 
is the relative change of place in one or more moving bodies. 
Retarded motion is that which suffers continual diminution of 
velocity, the laws of which are the reverse of those of accelerated 
motion. Rotary motion, turning as a wheel on its axis, pertain¬ 
ing to or resembling the motion of a wheel. Rotary motions 
were favorite ones with ancient philosophers. They considered a 
circle as the most perfect of all figures, and erroneously concluded 
that a body in motion would naturally revolve in one. 

To the substitution of circular for straight motions, and of 
continuous for alternating ones, may be attributed nearly all the 
conveniences and elegancies of civilized life. It is not too much 
to assert, that the present advanced state of science and the arts 
is due to revolving mechanism. From the earliest times it had 
been an object to convert, whenever practicable, the rectilinear 
and reciprocating movements of machines into circular and con¬ 
tinuous ones. Old mechanics seem to have been led to this result 
by that tact or natural sagacity, that is more or less common to 


all times and people. Thus the dragging of heavy loads on the 
ground led to the adoption of wheels and rollers,— hence carts 
and carriages. The rotary movements of the drill superseded the 
alternating one of the punch and gouge, in making perforations; 
the whetstone gave way to the revolving grindstone; the turning- 
lathe produced round forms infinitely more accurate and more ex¬ 
peditiously than the uncertain and irregular carving or cutting 
with the knife. Motion is uniform, when a body moves continually 
with the same velocity, passing over equal spaces in equal times. 

Oscillation, Centre of. —The centre of oscillation is that point 
in a vibrating body, in which, if the whole were concentrated and 
attached to the same axis of motion, it would vibrate in the same 
time the body does in its natural state. The centre of oscillation 
is situated in a right line passing through the centre of gravity, 
and perpendicular to the axis of motion. 

Pendulum. — If any heavy body, suspended by an inflexible 
rod from a fixed point, be drawn aside from the vertical position, 
and then let fall, it will describe the arc of a circle, of which 
the point of suspension is the centre. On reaching the vertical 
position, it will have acquired a velocity equal to that which it 
would have acquired by falling vertically through the versed sine 
of the arc which it has described, in consequence of which it will 
continue to move in the same arc until the whole velocity is de¬ 
stroyed ; and, if no other force than gravity were in operation, 
this would take place, when the body reached a height on the 
opposite side of the vertical height, equal to that from which it 
fell. Having reached this height, it would again descend, and so 
continue to vibrate forever; but, in consequence of the friction 
of the axis and the resistance of the air, each successive vibration 
will be diminished, and the body soon be brought to rest in 
the vertical position. A body thus suspended and caused to vi¬ 
brate is called a pendulum; and the passage from the greatest 
distance from the vertical on the one side to the greatest distance 
on the other is called an oscillation. 

Percussion. — The centre of percussion is that point in a body 


604 


THE ENGINEER^ HANDY-BOOK. 


revolving about an axis at which, if it struck an immovable ob¬ 
stacle, all its motion would be destroyed, or it would not incline 
either way. When an oscillating body vibrates with a given 
angular velocity, and strikes an obstacle, the effect of the impact 
will be the greatest, if it be made at the centre of percussion; 
since, in this case, the obstacle receives the whole revolving mo¬ 
tion of the body; whereas, if the blow be struck at any other 
point, a part of the motion will be employed in endeavoring to 
continue the rotation. 

Perpetual Motion. — In mechanics, a machine which, when set 
in motion, would continue to move forever, or, at least, until de¬ 
stroyed by the friction of its parts, without the aid of any exterior 
cause, would constitute perpetual motion. The discovery of 
perpetual motion has always been a celebrated problem in me¬ 
chanics, on which many ingenious, though in general ill-instructed, 
persons have spent their time; but all the labor bestowed on it 
has proved abortive. In fact, the impossibility of its existence 
has been fully demonstrated from the known laws of matter. In 
speaking of perpetual motion, it is to be understood that, from 
among the forces by which motion may be produced, we are to 
exclude not only air and water, but other natural agents, as heat, 
atmospheric changes, etc. The only admissible agents are the 
inertia of matter, and its attractive forces, which may all be con¬ 
sidered of the same kind as gravitation. It is an admitted prin¬ 
ciple in philosophy, that action and reaction are equal, and that, 
when motion is communicated from one body to another, the first 
loses just as much as is gained by the second. But every moving 
body is continually retarded by two passive forces,— the resist¬ 
ance of the air and friction. In order, therefore, that motion 
may be continued without diminution, one of two things is neces¬ 
sary— either that it be maintained by an exterior force, (in which 
case it would cease to be what we understand by a perpetual mo¬ 
tion,) or that the resistance of the air and friction be annihilated, 
which is practically impossible. 

The motion cannot be perpetuated, till these retarding forces 


THE ENGINEER’S HANDY-BOOK. 


605 


are compensated, and they can only be compensated by an exterior 
force, as the force, communicated to any body, cannot be greater 
than the generating force, which is only sufficient to continue the 
same quantity of motion, when there is no resistance. The error, 
of confounding mere pressure with energy available to produce 
power, is the main origin of the majority of attempts at perpetual 
motion, and even sometimes causes, among confused minds, ex¬ 
aggerated expectations about the effects to be obtained from me¬ 
chanical contrivances. A wound-up spring is exactly equivalent 
to a weight. It may exert a certain pressure, great in proportion 
to its size and strength; but, unless it is allowed to unwind it, it 
cannot produce motion or power. It is the same with compressed 
air or gases; they are, in fact, nothing but wound-up springs, with 
this difference, however, that, in place of needing mechanical power 
to wind them up, we may use either heat, chemical agencies, or 
electricity. 

Pneumatics. —Pneumatics is the science which treats of the 
mechanical properties of elastic fluids, and particularly of atmo¬ 
spheric air. Elastic fluids are divided into two classes — perma¬ 
nent gases and vapors. The gases cannot be converted into the 
liquid state by any known process; whereas the vapors are readily 
reduced to the liquid form by pressure or diminution of tempera¬ 
ture. In respect to their mechanical properties, there is, however, 
no essential difference between the two classes. Elastic fluids, in 
a state of equilibrium, are subject to the action of two forces, 
namely, gravity, and a molecular force acting from particle to 
particle. Gravity acts on the gases in the same manner as on all 
other substances; but the action of the molecular forces is alto¬ 
gether different from that which takes place among the elementary 
particles of solids and liquids; for, in the case of solid bodies, the 
molecules strongly attract each other (whence results their co¬ 
hesion), and, in the case of liquids, exert a feeble or evanescent 
attraction, so as to be indifferent to internal motion; but, in the 
case of the gases, the molecular forces are repulsive, and the mole¬ 
cules, yielding to the action of these forces, tend incessantly to 
51* 


606 


THE ENGINEER^ HANDY-BOOK. 


recede from each other, and, in fact, do recede until their further 
separation is prevented by an exterior obstacle. Thus air, con¬ 
fined within a close vessel, exerts a constant pressure against the 
interior surface, which is not sensible, only because it is balanced 
by the equal pressure of the atmosphere on the exterior surface. 
This pressure exerted by the air against the sides of a vessel, within 
which it is confined, is called its elasticity — its elastic force or 
tension. 

Power. — Power is the product of force and velocity; that is 
to say, a force multiplied by the velocity with which it is acting. 
The term horse-power is a unit of power, equivalent to a force of 
33,000 pounds acting with a velocity of one foot per minute, or 
150 pounds acting with a velocity of 220 feet per minute, which 
is the same as a force of 550 pounds acting with a velocity of one 
foot per second. Man-power is a unit of power established by 
Morin to be equivalent to 50 foot-pounds of power, or 50 effects; 
that is to say, a man turning a crank with a force of 50 pounds, 
with a velocity of one foot per second, is a standard man-power. 

Power implies the ability to do so much work in a certain time , 
and, like other things which we talk about and compare, requires 
a unit by which to measure it. The unit used in this country is 
called a horse-power, and is equal to raising 33,000 lbs. through 
a space of one foot in a minute of time, or in any other way per¬ 
forming 33,000 foot-pounds of work in a minute. 

Pressure. — Pressure is force acting against some obstacle or 
opposing force. It differs from weight, inasmuch as pressure 
exerts a force in all directions, whereas weight exerts its influ¬ 
ence only in one. There are instances where weight causes press¬ 
ure in more than one direction, e. g in fluids, while there are 
others in which pressure has no connection with weight, such as 
the pressure of steam in a boiler. 

Prime Movers. —Prime movers are those machines from which 
we obtain power through their adaptation to the transformation 
of some available natural force into that kind of effort which de¬ 
velops mechanical power. 



THE ENGINEER’S HANDY-BOOK. 


607 


The Pulley. —Pulleys are of two kinds , fixed and movable. The 
fixed pulley only turns upon its axis, and affords no mechanical 
advantage; therefore, when the power and the weight are equal, 
they balance each other. It is used for the convenience of chang¬ 
ing the direction of a motion. The movable pulley not only turns 
upon its axis, but rises and falls with its weight. Every movable 
pulley may be considered as hanging by two ropes equally stretched, 
and which, consequently, are equal portions of the weight; there¬ 
fore each pulley of this sort doubles the power. The principle of 
the pulley, as practically applied in the block and tackle, is the 
distribution of weight on various points of support, the mechani¬ 
cal advantage derived depending entirely upon the flexibility and 
tension of the rope and the number of pulleys or sheaves in the 
lower or rising block. Hence, by blocks and tackle of the usual 
kind, the power is to the weight as the number of cords attached 
to the lower block. The advantages to be gained by the employ¬ 
ment of the block and tackle may be found by dividing the weight 
to be raised by the number of cords leading to, from, or attached 
to the lower block, and the quotient is the power required to pro¬ 
duce an equilibrium, provided friction does not exist. Or, divide 
the weight to be raised by the power to be applied ; the quotient 
is the number of sheaves in, or cords attached to, the rising block. 

The Screw. —The screw is another modification of the inclined 
plane, and it may be said to remove the same kind of practical 
inconveniences incidental to the use of the latter, that the pulley 
does in reference to the simple lever. The lever is very limited 
in the extent of its action; so is the inclined plane. But the pul¬ 
ley multiplies the extent of the action of the lever, by presenting^ 
in effect, a series of levers acting in regular succession ; and just 
such a purpose is effected by the screw. It multiplies the extent 
of the action of the inclined plane by presenting, in effect, a con¬ 
tinued series of planes. 

The screw; in principle, is that of an inclined plane wound 
round a cylinder, which generates a spiral of uniform inclination, 
each revolution producing a rise or traverse motion equal to the 


608 


i 


THE ENGINEER^ HANDY-BOOK. 


pitch of the screw or distance between the two consecutive threads, 
the pitch being the height or angle of inclination, and the circum¬ 
ference the length of the plane. Hence, the mechanical advan¬ 
tage is as the circumference of the circle described by the lever 
where the power acts is to the pitch of the screw, so is the force 
to the resistance in principle. 

To find the effective power obtained by a screw of |--inch pitch, 
and moved by a force equal to 50 lbs. at the extremity of a lever 
30 inches in length : 


30 x 2 x 3-1416 x 50 
* 875 


= 10,760 lbs. 


To find the power necessary to overcome a resistance equal to 
7000 lbs. by a screw of lj-inch pitch, and moved by a lever 25 
inches in length: 


7000x1*25 


= 55-73 lbs. 


25 x 2 x 3-1416 


In the case of a screw acting upon the periphery of a toothed 
wheel, the power is to the resistance as the product of the circle’s 
circumference described by the winch or lever and radius of the 
wheel to the product of the screw’s pitch and radius of the axle, 
or point whence the power is transmitted ; but observe that, if the 
screw consist of more than one thread, the apparent pitch must 
be increased so many times as there are threads in the screw. 
Hence, to find what weight a given power will equipoise, multiply 
together the radius of the wheel, the length of the lever at which 
the power acts, the magnitude of the power, and the constant 
number 6*2832; divide the product by the radius of the axle into 
the pitch of the screw, and the quotient is the weight that the 
power is equal to. 

Resilience is a characteristic of bodies, which manifests a cer¬ 
tain degree of flexibility before they can be broken, hence the 
body that bends or yields the most at the time of fracture is the 
toughest. 

Statics is the science of forces in equilibrium. It treats of the 
strength of materials, of bridges, and of girders; the stability of 




THE ENGINEER’S HANDY-BOOK. 


609 


walls, steeples, and towers; the static momentum of levers, with 
their combinations into weighing-scales, windlasses, pulleys, fu¬ 
nicular machines, inclined planes, screws, catenaria, and all kinds 
of gearing. 

Strength. —Strength is the resistance which a body opposes to 
a disintegration or separation of its parts. Tensile strength is the 
absolute resistance which a body makes to being torn apart by 
two forces acting in opposite directions. Crushing strength is the 
resistance which a body opposes to being battered or flattened 
down by any weight placed upon it. Transverse strength is the 
resistance to bending, or flexure, as it is called. Torsional strength 
is the resistance which a body offers to any external force which 
attempts to twist it round. Detrusive strength is the resistance 
which a body offers to being clipped or shorn into two parts by 
such instruments as shears or scissors. Working strength. The 
term “working strength” implies a certain reduction made in the 
estimate of the strength of materials, so that, when the instrument 
or machine is put to use, it may be capable of resisting a greater 
strain than it is expected on the average to sustain. 

Tools. —By the term tools, according to the definition given 
by Rennie, we understand instruments employed in the manual 
arts for facilitating mechanical operations, by means of percus¬ 
sion, penetration, separation, and abrasion, of the substances 
operated upon, and for all which operations various motions are 
required to be imparted either to the tool or to the work. 

Torsion. — Torsion, in mechanics, is the twisting or wrenching 
of a body by the exertion of a lateral force. If a slender rod of 
metal, suspended vertically, and having its upper end fixed, be 
twisted through a certain angle by a force acting in a plane per¬ 
pendicular to its axis, it will, on the removal of the force, untwist 
itself, or return in the opposite direction with a greater or less 
velocity, and, after a series of oscillations, will come to rest in its 
original position. The limits of torsion, within which the body 
will return to its original state, depend on its elasticity. A fine 
wire of a few feet in length may be twisted through several revo- 

20 


610 


THE ENGINEER’S HANDY-BOOK. 


lutions, without impairing its elasticity; and, within those limits, 
the force evolved is found to be perfectly regular, and directly 
proportional to the angular displacement from the position of rest. 
If the angular displacement exceeds a certain limit (as in a wire 
of lead, for example, before disruption takes place), the particles 
will assume a new arrangement, or take a set, and will not return 
to their original position on the withdrawal of the disturbing force. 

Velocity. —Velocity is the rate of motion. Velocity is inde¬ 
pendent of space and time, but, in order to obtain its value or 
expression as a quantity, we compare space with time. Thus, 
when the value of the velocity of a moving body is required, we 
measure the space which the body passes through, and divide 
that space by the time of passage, and the quotient is the velocity. 

Weight. — The weight of a body is the force of attraction be¬ 
tween the earth and that body. The weight of a body is greatest 
at the surface of the earth, and decreases above or below that 
surface. Above the surface, the weight decreases as the square 
of its distance from the centre of the earth, and below the surface 
the weight decreases simply as its distance from the centre. 

Weights and Measures. — The weights and measures of this 
country are identical with those of England. In both countries 
they repose, in fact, upon actually existing masses of metal (brass), 
which have been individually declared by law to be the units of 
the system. In scientific theory, they are supposed to rest upon a 
permanent and universal law of nature — the gravitation of dis¬ 
tilled water at a certain temperature and under a certain atmos¬ 
pheric pressure. In this aspect, the origination is with the grains, 
which must be such that 252,458 of these units of brass will be 
in just equilibrium with a cubic inch of distilled water, when the 
mercury stands at 30 inches in a barometer, and at 62 degrees in 
a thermometer of Fall. Unfortunately, the expounders of this 
theory in England used only the generic term brass, and failed to 
define the specific gravity of the metal to be employed; the con¬ 
sequence of this omission is to leave room for an error of yooVoo 
in every attempt to reproduce or compare the results. This is the 


1 





THE ENGINEER’S HANDY-BOOK. 


611 


minimum possible error; the maximum would be a fraction of the 
difference in specific gravity between the heaviest and lightest 
brass that can be cast. 

The Wheel and Axle. —The wheel and axle may be considered 
as a perpetual lever, from the constant renewal of the points of 
suspension and resistance. The fulcrum is the centre of the axis, 
the longer arm is the radius of the wheel, and the shorter arm the 
radius of the axis. As the diameters of different circles bear the 
same proportion to each other that their respective circumferences 
do, the power is also to the weight as the diameter of the wheel is 
to the diameter of the axle. If one wheel move another of equal 
circumference, no power will be gained, as they will both move 
equally fast. But if one wheel move another of different diameter, 
whether larger or smaller, the velocities with which they move will 
be inversely as their diameters, circumferences, or number of teeth. 

The Wedge. —The wedge is a double inclined plane, conse¬ 
quently its principles are the same. Hence, when two bodies are 
forced asunder, by means of the wedge, in a direction parallel to 
its head, multiply the resisting power by half the thickness of the 
head or back of the wedge, and divide the product by the length 
of one of its inclined sides; the quotient is the force equal to the 
resistance. The breadth of the back or head of a wedge being 3 
inches, its inclined sides each 10 inches, required the power neces¬ 
sary to act upon the wedge so as to separate two substances whose 

150 x 1*5 

resisting force is equal to 150 lbs. *——-— 22‘5 lbs. 

Work is a term in mechanics of recent origin, but of great 
utility; it means a compound of force, pressure, and motion. 
Work is said to be performed when a pressure is exerted upon a 
body, and the body is thereby moved through space. The unit 
of pressure is a pound, the unit of space a foot; and work is 
measured by a foot-pound as a unit. Thus, if a pressure of so 
many pounds be exerted through a space of so many feet, the 
number of pounds is multiplied into the number of feet, and the 
product is the number of foot-pounds of work. 



G12 


HANDY-BOOK 


THE ENGINEER’S 

Metals and Alloys. 

TABLE 


OF MINERAL SUBSTANCES AND THEIR CHEMICAL EQUIVALENTS. 


Names. 

New Atomic 
Weights. 

i 

Old Atomic 
Weights. 

Names. 

New Atomic 
W eights. 

Old Atomic 
Weights. 

Aluminium. 

Antimony. 

Arsenic. 

Barium. 

Beryllium, or) 
Glucinium J 

Bismuth. 

Boron. 

Bromine. 

Cadmium. 

Caesium. 

Calcium. 

Carbon. 

Cerium. 

Chlorine. 

Chromium. 

Cobalt. 

Columbium, ) 
or Niobium J 

Copper. 

Didymium. 

Erbium . 

Fluorine. 

Gallium. 

Glucinium,or) 
Beryllium../ 

Gold. 

Hydrogen. 

Indium. 

Iodine. 

Iridium. 

Iron. 

Lanthamum ... 

Lead. 

Lithium. 

Magnesium. 

27*4 

122-0 

750 

137-0 

9*0 

209-0 

10-9 

80-0 

112-0 

133-0 

40-0 

12-0 

92-0 

35-5 

52-5 

59-0 

94*0 

63*4 

96-0 

112*6 

19-0 

9-0 

196- 0 

2-0 

114-0 

127-0 

197- 2 
56-0 

139-0 

207-0 

7*0 

24-3 

13*7 

122-0 

75-0 

68- 5 

4'5 

209-0 

10*9 

80-0 

56- 0 
133*0 

20*0 

6-0 

46*0 

35-5 

26-25 

29-5 

94-0 

31-7 

48-0 

19-0 

4-5 

98*0 

1-0 

57- 0 
127-0 

98-6 

28-0 

69- 5 
103-5 

7*0 

12*15 

Manganese. 

Mercury. 

Molybdenum... 

Nickel. 

Niobium, or) 
ColumbiumJ 

Nitrogen. 

Osmium. 

Oxygen. 

Palladium. 

Phosphorus. ... 

Platinum. 

Potassium. 

Rhodium. 

Rubidium. 

Ruthenium. 

Selenium. 

Silicon. 

Silver. 

Sodium. 

Strontium. 

Sulphur. 

Tantalum. 

Tellurium. 

Terbium. 

Thallium. 

Thorium. 

Tin. 

Titanium. 

Tungsten. 

Uranium. 

Vanadium. 

Yttrium. 

Zinc. 

Zirconium. 

55-0 

200-0 

96-0 

59-0 

94-0 

14-0 

199-0 

16-0 

106-5 

31- 0 
197-4 

39-11 

104-0 

85*5 

104-0 

79-5 

28'0 

108-0 

23-0 

87-5 

32- 0 
182-0 
129-0 
148*5 
204*0 
231-0 
118-0 

50- 0 
184*0 
120-0 

51- 0 
92-5 
65-0 
89-5 

27'5 

100-0 

48-0 

29-5 

94-0 

14-0 

99-5 

8'0 

53-25 

31-0 

98-7 

39-11 

52-0 

85'5 

52*0 

39-75 

14-0 

108-0 

23-0 

43-8 

16-0 

182-0 

64-5 

74-2 

204-0 

59- 0 
25'0 
92'0 

60- 0 
51-0 
46’25 
32*5 
4P75 


Iron is the most important of all the metals known to man, as 
well as the most useful. It has been one of the principal agents 


























































































THE ENGINEER’S HANDY-BOOK. 


613 


in the civilization of the human race, and is at the present day 
more extensively employed in the mechanical arts than any other 
metal. It is found in different conditions, but always in the state 
of oxides, or as iron ore, that is, a sort of rusty metallic state. The 
most common kind — the hematite or blood-stone — may be de¬ 
scribed as iron-rust solidified, or rendered concrete by water. After 
being taken from the ground in the condition of ore, it is placed 
in a blast-furnace and smelted, after which it is rendered fibrous 
and ductile by puddling. Spiegel iron or specular cast-iron is, as 
its name implies, largely crystalline, presenting bright, mirror-like, 
cleavage planes. 

Wrought-iron varies in specific gravity from 7*8 to 7*6; taking 
the mean at 7*7, a cubic foot will weigh 479*8721664 lbs., or nearly 
480 lbs. Cast-iron varies in specific gravity from 7*5 to 6*9, the 
average being 7*2. 



Wrought-iron, Lbs. 

Cast-Iron, Lbs. 

A cubic foot. 

479*872 

439*800 

A cylindrical foot. 

376*891 

344*407 

A spherical foot. 

251*261 

230*279 

A cubic inch. 

0*2777 

0*2845 

A cylindrical inch— 

0*2181 

0*1999 

A spherical inch...... 

• 0*1454 

0*1333 


Cast-iron is composed of about 91 per cent, of iron, 5 of car¬ 
bon, 2 of silicon, and 2 parts of sulphur phosphorus, and other 
impurities. It also contains manganese, nickel, cobalt, chromium, 
vanadium, titanium, and tungsten, in minute quantities. The 
parts of steam-engines generally made of wrought-iron are the 
link, eccentric-rods and straps, valve- and piston-rods, connecting- 
rods, air-pump levers, cross-heads for pumps, arms, etc. 

Rust. — The red powder that falls from iron which has long 
been subjected to the action of moisture, is the oxide of the metal, 
and is termed rust. 

Steel is one of the chemical modifications of iron, a combina¬ 
tion of iron and carbon. It is composed of 98*6 of iron and 1*4 

62 













614 


THE ENGINEER’S HANDY-BOOK. 


of carbon. The steel containing the least carbon is the softest, 
and that containing the most is .the hardest. 

Cast-iron, wrought-iron, and steel can be distinguished from 
each other by the difference in the grain — wrought-iron being finer 
in the grain than cast, and steel finer than wrought; cast-iron be¬ 
ing short and brittle, wrought-iron fibrous, and steel void of fibre. 

Steel and cast-iron are fusible; wrought-iron is malleable,duc¬ 
tile, tough, fibrous, and possesses the quality of welding; steel, 
also, is capable of being welded. From this it will be seen, that 
steel possesses properties in common with both wrought- and cast- 
iron. Malleable iron is composed of 99'5 per cent, of iron, 0035 
of carbon, 0‘076 of silicon, and the rest is sulphur and phos¬ 
phorus. Its principal value consists in its property of resisting 
the chemical action of salt water or steam. 


TABLE 

SHOWING THE HEAT-CONDUCTING PROPERTIES OF DIFFERENT METALS. 


Copper 

• 

• 

Conductive Property 
for Transmission of 
Heat. 

. 1000. 

Brass . 

• 

• 

. 468. 

Wrought-iron 

• 

• 

. 336. 

Cast-Iron 

• 

• 

. 311. 


From the above, it is evident that copper possesses the highest 
conducting properties. 

TABLE 


SHOWING THE TENACITY OR TENSILE 

Copper (cast) 

Brass (cast) 

Gun-Metal (cast) 

Iron, Wrought . 

Iron, Cast . 


STRENGTH OF DIFFERENT METALS. 

Tenacity in Lbs. 
per Square Inch. 

19,000. 

18,000. 

. . 36,000. 

. 51,000 to 61,000. 

20 , 000 . 






THE ENGINEER’S HANDY-BOOK. 


615 


Brass or gun-metal is used for main-bearings of marine-engines 
and propeller-shafts, link-blocks, air-pump buckets, head- and foot- 
valves, stern-tube bushes, propellers, and steam- and water-cocks. 
White metal is frequently used as a lining for main propeller- 
shaft and tunnel-bearings. Its chief value consists in its anti¬ 
friction and lubricating properties, while its disadvantages are 
that, if it becomes overheated, it will melt and run out of the 
bearing. Muntz metal is used for surface-condenser tubes, air- 
and circulating-pump rods, and surface-condenser tube-plates. It 
is malleable, has a high tensile strength, is very durable, and not 
liable to corrosion. 

TABLE 


SHOWING THE PROPORTION OF CARBON IN THE VARIOUS GRADES OF 

IRON AND STEEL. 

Iron semi-steelified contains . . . 1-150 of Carbon. 


Soft steel capable of welding . 

. 1-120 

Cast steel for common purposes 

. 1-100 

Cast steel requiring more hardness . 

. 1-90 

Steel capable of standing a few blows, 


but quite unfit for drawing . 

. 1-50 

First approach to a steely, granulated 


fracture ..... 

. 1-40 

White cast-iron .... 

. 1-25 

Mottled cast-iron .... 

. 1-20 

Carbonated cast-iron 

. 1-15 

Super-carbonated crude iron 

. 1-12 


<< 

« 

<( 


<< 


<< 


Copper is softer and more ductile than iron, is easily melted, 
and, when cast, is almost always free from blisters and sound. 
Its chief drawback is its cost and great weight, which are nearly 
double that of iron.. Its superior conducting power is to some 
extent offset by the greater thickness required for strength. 

Sulphur is less influenced by changes of temperature than any 
known mineral. It has a strong affinity for iron, and, as there is 
a great deal of it in bituminous coal, the sulphuretted hydrogen 
gas, disengaged from the fuel, attacks and soon destroys the metal. 






616 


THE ENGINEER’S HANDY-BOOK. 


Babbitt’s Metal. — Its composition is as follows: Four pounds 
of copper, eight pounds of regulus of antimony, and eighty-eight 
pounds of tin. The copper is first melted; the tin and the regu¬ 
lus of antimony are then added. After the metals have been 
fused a short time, and brought to a dull red heat, it is fit for use. 

Another durable alloy for the journal-boxes of steam-engines, is 
copper, 84; zinc, 8; tin, 2; lead, 4; and iron, 5 parts. 

Bronze Alloy. — Copper, 80 ; tin, 18; zinc, 2. If, after cast¬ 
ing, and while still red hot, cold water is poured over it, it becomes 
harder, and finer in grain, and tougher, as the tin, instead of sepa¬ 
rating, as happens, when the brouze cools slowly, remains mixed, 
and the alloy retains its compactness. 


Alloys and Compositions. 



U 

<D 



fl 

O 

r* 



D 

• , 

a, 

o 

O 

G 

a 

a 

0? 


3 

t— 


O 

ts 

H 

•< 

Hi 

£ 

S 

Brass for locomotive bearings. 

50* 

2-5 

5- 


5 



Brass for glands. 

65- 

0-5 

8* 





Brass engine bearings. 

50* 

1-8 

6*5 





Yellow brass for turning. 

40* 

20- 






Brass richer. 

50* 

10- 






Box metal. 

80* 

10- 






Red brass. 

70* 

10- 



5 



Flanges to stand brazing. 

64* 

2- 



O 



Tough brass engine work. 

100- 

15* 

15* 





Tough brass for heavy bearings.. 

160* 

5- 

25* 





Muntz metal . 

90* 

60- 






White metal . 

11* 

11* 

42-6 

85*2 




White metal, hard. 

104*7 

38*7 

6-6 





Bronze red . 

130-5 

19*5 






Bronze yellow . 

100-8 

46*8 

2-4 





Gun metal for bearings. 

90-3 

9-67 

0-3 





Bell metal for larw. hells. 

80" 


20* 





Britannia metal . 

1- 

2* 

81- 

16* 




Brass for sheets . 

81-7 

15-3 





s 

Nickel-silver, English. 

60 * 

17-8 




22*2 


Nickel-silver Parisian. 

66 * 

13G 




19*3 


German silver. 

50- 

25* 




25- 




1 

















































THE ENGINEER’S HANDY-BOOK. 


617 


Solder. 

Silver solder is generally composed of 4 parts silver and 2 
parts yellow brass. Pure copper, in thin strips, is generally used 
for soldering-irons. Plumbers’ solder is composed of 2 parts tin 
and 4 parts lead. This solder melts at about 450° Fah. Tin¬ 
smiths’ solder is composed of 4 parts tin and 2 parts lead. This 
solder melts at about 350° Fah. Bismuth solder is composed 
of 7 parts bismuth, 5 parts lead, and 3 parts tin. This solder melts 
at about 225° Fah. All tin and lead solders become more fusible 
the more tin they contain. Thus, 1 part tin and 10 parts lead 
melt at about 550° Fah.; while 6 parts tin and 1 part lead melt 
at about 375° Fah. All the tin, lead, and bismuth solders become 
more fusible the more lead and bismuth they contain. 


TABLE 


SHOWING THE AVERAGE CRUSHING LOAD OF DIFFERENT MATERIALS, 
OR THE WEIGHT UNDER WHICH THEY WILL CRUMBLE. 


Alder . . . 

Ash .... 
Beech . . . 

Cedar . . . 

Elm . . . . 

Fir— Spruce 
Hickory (white) 
Hornbeam 
Larch- . 

Locust . . . 

Maple . . . 

Oak .... 

“ English . 
Pine (pitch) . 

“ Am. yellow 
Poplar . . . 

Plum . . . 

Sycamore . . 

Teak . . . 


Lbs. per Sq. Inch. 


6,900 

8,600 

7,600 

5.700 
10,000 

6.500 
8,925 

4.500 

3.200 
9,113 
8,150 

4.200 

6.500 
6,800 
5,300 
5,100 

3.700 
7,000 

12,000 


Lbs. per Sq. Inch. 

Walnut .... 

. 6,000 

Willow .... 

. 2,900 

Cast iron, Am. . . 

. 174,803 

Low moor, Eng . . 

. 62,450 

Wrought-iron 

. 38,000 

Steel, cast .... 

. 225,000 

“ tempered . . 

. 337,800 

Copper, cast . . . 

.117,000 

Brass, “ ... 

.464,800 

Tin, “ . . , 

. 15,500 

Lead. 

. 7,730 

Hard brick . . . 

. 2,000 

Crown glass . . . 

. 31,000 

Granite, Eng.. . . 

. 10,360 

Portland cement 

. 15,000 

Freestone, Conn. 

. 3,522 

Marble, Am. . . . 

. 18,061 

Roman cement . . 

342 


52 * 



























618 


THE ENGINEER’S HANDY-BOOK 


TABLE 

SHOWING THE TENSILE STRENGTH, OR THE STRAIN THAT WILL PULL 
DIFFERENT METALS ASUNDER ON A STRAIGHT PULL. 


Antimony . 

Bismuth 
Brass — cast 
Copper — cast 
Gun-metal, copper, and 
Iron — cast . 

W rough t-iron — bar 

- good . 

-superior 

-best American 

-low moor 

-boiler-plate . 

-rivet — English 

Steel plates — English 


tin . 


Lbs. per 
Sq. Inch. 

1,000 

3,200 

18,000 

19,000 

96,000 

17,900 

57,500 

60,000 

70,000 

76,160 

60,000 

45,000 

65,000 

78,000 


Steel plates—Hussey, Wells 
& Co.—American . 

- Bessemer—American 

Bessemer steel — tool . 
Steel, bar—Black Diamond 
—American 

-tempered 

Ch rome steel — A merican . 
Silver — cast 
Tin — block 
Zinc — cast . 

“ sheet 

“ wire 


Lbs. per 
Sq. Inch. 


94,450 

98,600 

112,000 

120,700 

214,400 

180,000 

41,000 

4,600 

2,800 

16,000 

22,000 


TABLE 

SHOWING THE TENSILE STRENGTH OF DIFFERENT KINDS OF WOOD. 


Alder 


Lbs. per 
Sq. Inch. 

. 14,000 

Hickory 



Lbs. per 
Sq. Inch. 

. 11,000 

Ash 


. 16,000 

Lignum-Vitae 



. 11,000 

Birch 


. 15,000 

Larch . 



. 7,000 

Bay wood 


. 12,000 

Locust . 



. 18,000 

Beech . 


. 11,500 

Maple . 



. 10,000 

Bamboo 


. 6,000 

Mahogany 



. 8,000 

Boxwood 


. 20,000 

Oak 



. 10,000 

Cedar 


. 7,000 

Pear 



. 10,000 

Chestnut 


. 13,000 

Pine 



. 10,000 

Cypress . 


. 6,000 

Poplar . 

• 


. 7,000 

Elder 


. 10,000 

Sycamore 



. 12,000 

Elm 


. 6,000 

Teak 



. 15,000 

Fir or Spruce 


. 10,000 

Walnut . 



. 8,000 

Hazel . 


. 18,000 

Yew 



. 8,000 

Holly . 


. 16,000 




























THE ENGINEER’S HANDY-BOOK. 619 

Black Finish for Brass. —-Make a strong solution of nitrate of 
silver in one dish and nitrate of copper in another. Mix the two 
together and plunge the brass into it. Now heat the brass 
evenly until the required degree of dead blackness is obtained. 
This is the method used by French instrument-makers to pro¬ 
duce the beautiful dead-black color so much admired in optical 
instruments. 

Lacquer for Brass Castings. —Take of shellac, 6 oz.; amber 
of copal, ground, 2 oz.; dragon’s blood, 40 grains; extract of red 

a 

sandal-wood, 30 grains; oriental saffron, 36 grains; pounded glass, 
4 oz.; very pure alcohol, 44 oz. To apply to brass, expose to a 
gentle heat and dip them in. 

Solder. —The following solder will braze steel or iron, and may 
be found very useful in case of a valve-stem or other light portion 
of an engine or machine breaking at a time when it is important 
that the engine or machine should continue work: Silver, 19 
parts; copper, 1 part; brass, 2 parts. 

Fusible Metal, consisting of 8 parts of bismuth, 5 of lead, and 
3 of tin. It melts at the heat of boiling water, or 212° Fall. By 
the addition of a very little mercury, it becomes still more fusible, 
and is used for certain anatomical injections and for the filling of 
carious teeth. 

Rule for finding the approximate weight of iron castings from pat¬ 
terns .— Multiply the weight of the pattern by the figures corre¬ 
sponding to the material in the table. Very accurate results can¬ 
not be expected, as the specific gravity of wood as well as of iron 
varies. 


Pine wood 



• 



. 14*0 

Oak “ 






. 9-0 

Beech “ 






. 9*7 

Linden “ 






. 13-4 

Birch “ 






. 10*6 

Alder “ 






. 12-6 

Pear-tree wood 


• 



• 

. 10-0 












620 


THE ENGINEER’S HANDY-BOOK 


TABLE 

SHOWING THE WEIGHT OF CASTINGS BY WEIGHT OF THE PATTERNS. 

Multiply the weight of the pattern by the multiplier opposite 
eacli material. 

. Cast-iron. 

. Wrought-iron. 

. Steel. 

. Copper. 

. Lead. 


White Pine X 16 

“ x 171 

“ x 17*3 

“ x 18 

“ x 25 


TABLE 

SHOWING THE SHRINKAGE OF CASTINGS OF DIFFERENT METALS. 


Cast-iron, -J- inch per lineal foot. 
Brass, T 3 g 
Lead, 4- 


44 

44 


Tin, inch per lineal foot. 
Zinc, 


TAB LE 

SHOWING THE WEIGHT AND BULK OF DIFFERENT SUBSTANCES IN CUBIC 

FEET, POUNDS AND TONS. 


Names of Substances. 

Pounds 
in One 
Cubic 
Foot. 

Cubic 
Feet in 
one gross 
Ton. 

Names of Substances. 

Pounds 
in One 
Cubic 
Foot. 

Cubic 
Feet in 
one gross 
Ton. 

Cast-iron .... 

450-5 

4-97 

Oak, white . . . 

45*2 

49-5 

Wrought-iron . . 

486-6 

4-60 

Clay. 

101-3 

22-1 

Steel . 

489-8 

4'57 

Concrete, ordinary 

115-0 

19-5 | 

Copper .... 

555 0 

403 

Brick. 

ioo-o 

22*4 

Lead. 

707-0 

3-16 

Plaster, Paris . . 

105-0 

2P3 

Brass. 

537*7 

4-16 

Sand. 

94-5 

23-7 

Tin. 

456-0 

4-91 

Granite .... 

1390 

16-1 

Pine, white . . . 

29-56 

75-6 

Earth, loose. . . 

78-6 

28-5 

“ yellow . . 

33-81 

66-2 

Water, salt (sea) . 

64-3 

34-8 

Mahogany . . . 

66-4 

33-8 

Water, fresh 

62-5 

35-9 

Marble, common . 

141-0 

15-9 

Ice. 

58-08 

38-56 

Millstone. ... 

130-0 

17-2 

Gold. 

1013-0 

2-21 

Oak, live .... 

70-0 

32-0 

Silver. 

551-0 

4-07 












































THE ENGINEER’S HANDY-BOOK. 


621 


TABLE 


SHOWING THE WEIGHT OF DIFFERENT METALS PER CUBIC FOOT. 


Brass 


Lbs. 

. 525 

j 

Lead, cast 

• 

Lbs. 

. 710 

Copper . 


. 550 

Silver 

• 

. 655 

Gold . 


.1,210 

Steel 

• 

. 490 

Iron, cast 


. 450 

Tin, cast. 

• 

. 456 

Iron, wrought. 


. 485 

Zinc 

• 

. 450 


TABLE 

SHOWING THE ACTUAL EXTENSION OF WROUGHT-IRON AT VARIOUS 

TEMPERATURES. 

Deg. 

of Fah. Length. » 

32°.1* 

212 .1-0011356 

392 .1*0025757Surface becomes straw-colored, deep- 

672 .1*0043253 j- yellow, crimson, violet, purple, deep- 

752 .1*0063894 / blue, bright-purple. 

932 .1*0087730) Surface becomes dull, and then bright- 

1,112 .1*0114811 J red. 

2192 I'".'.." 1-0348242 } Bright ' red ’ yellow ’ welding heat, white 

2,732 . 1-0512815 ) Iieat 

2,912 .Cohesion destroyed. Fusion perfect. 

Linear Expansion of Wrought-lron. —The linear expansion 
which a bar of wrought-iron undergoes, according to Daniell’s 
pyrometer, when heated from the freezing- to the boiling-point, or 
from 32° to 212° Fah., is about of its length; at higher tem¬ 
peratures the elongation becomes more rapid. Thus, it will be 
seen how sensible a change takes place when iron undergoes a 
variation of temperature. A bar of iron 10 feet long, subject to 
an ordinary change of temperature of from 32° to 180° Fah., will 
elongate more than ^ of an inch, or sufficient to cause fracture in 
stone-work, strip the thread of a screw, or endanger a bridge, 






















622 


THE ENGINEER^ HANDY-BOOK. 


floor, roof, or truss, or even push out a wall if brought in contact 
with it. 

The expansion of volume and surface of wrought-iron is cal¬ 
culated by taking the linear expansion as unity; then, following 
the geometrical law, the superficial expansion is twice the linear, 
and the cubical expansion is three times the linear. 

» t » ■ • ■ 

Wrought-iron will bear on a square inch, without permanent 
alteration, 17,800 pounds, and an extension in length of yy\jy. 
Cohesive force is diminished 30 V 0 by an increase of one degree 
of heat. 

Compared with cast-iron, its strength is T12 times, its extensi¬ 
bility 0'86 times, and its stiffness 1*3 times. 

Cast-iron expands yg^ggy of its length for one degree of heat; 
the greatest change in the shade, in this climate, is yy^o °f its 
length ; exposed to the sun’s rays, yoVg- 

Cast-iron shrinks, in cooling, from to of its length. 

Cast-iron is crushed by a force of 93,000 pounds upon a square 
inch, and will bear, without permanent alteration, 15,300 pounds 
upon a square inch. 

To find the surface dilatation of any particular article, double 
its linear dilatation ; and to find the dilatation in volume, triple 
it. To find the elongation in linear inches, per linear foot, of any 
particular article, multiply its respective linear dilatation, as given 
in the table, by 12. 

TABLE 

SHOWING THE LINEAR DILATATION OF SOLIDS BY HEAT. 

Length which a Bar Heated at 212° has greater than when at the Temperature of 32°. 


Brass,cast..... 0018671 

Copper. 0017674 

Gold .. 0014880 

Iron, cast. 0011111 

Iron, wrought. 0012575 

Silver . 0020205 

Steel. 0011898 









THE ENGINEER’S HANDY-BOOK. 


623 


TABLE 

i 

DEDUCED FROM EXPERIMENTS ON IRON PLATES FOR STEAM-BOILERS, 
BY THE FRANKLIN INSTITUTE, PHILADA. 

Iron boiler-plate was found to increase in tenacity, as its tem¬ 
perature was raised, until it reached a temperature of 550° above 
the freezing-point, at which point its tenacity began to diminish. 
At 32° to 80° tenacity is 56,000 lbs., or below its maximum. 


it 

570° 

it 

“ 66,000 

it 

the maximum. 

a 

720° 

it 

“ 55,000 

it 

the same nearly as at 30° 

a 

1050° 

it 

“ 32,000 

if 

nearly ^ the maximum. 

a 

1240° 

it 

“ 22,000 

it 

nearly | the maximum. 

a 

1317° 

it 

“ 9,000 

it 

nearly j the maximum. 


It will be seen by the above table that if a boiler should become 
overheated by the accumulation of scale on some of its parts, or 
an insufficiency of water, the iron would soon become reduced to 
less than one-half its strength. 

TABLE 

SHOWING THE STRENGTH OF COPPER BOILER PLATES AT DIFFERENT 
TEMPERATURES, DEDUCED FROM EXPERIMENTS BY THE FRANKLIN IN¬ 
STITUTE OF PHILA. THE STANDARD STRENGTH AT 32° BEING 32,800 
LBS. PER SQUARE INCH. 



Temperature 
above 32°. 

Diminution of 
Strength. 


Temperature 
above 32°. 

Diminution of 
Strength. 

1 

•90° 

0-0175 

9 

660° 

0-3425 

2 

180 

0-0540 

10 

769 

0-4398 

3 

270 

0-0926 

11 

812 

0-4944 

4 

360 

0-1513 

1 12 

880 

0-5581 

5 

456 

0-2046 13 

989 

0-6691 

6 

460 

0-2133 

14 

1000 

0-6741 

7 

513 

0-2446 

15 

1200 

0*8861 

8 1 

532 

0-2558 

16 

1300 

1-000 


It will be seen from the above table, that, in being heated from 
the freezing-point to the boiling-point of water, copper loses 5 
per cent, of its strength; at 550° it loses about one-quarter of its 
strength ; and at 1332° loses all its tenacity. 















TABLE 

SHOWING THE WEIGHT OF CAST-IRON RALLS FROM 3 TO 13 INCHES IN DIAMETER 


624 


THE ENGINEER^ HANDY-BOOK. 


win 

r 

L— 

' CO 

H(N 

GO 

1- 

HO 

Hr 

Hn 

CM 


HO 


Hh 

t- 

L- 


r 

WlH 

<30 

CM 

He* 

can 

<30 

l>- 

CO 


He* 

<30 

CO 

CO 


Hr 

CO 

03 


<M 

Min' 

CO 

HO 

CM 

He* 

CO 

HO 

CM 

Hr 

o 

HO 

<N 

HO 

l>- 

rH 

min' 

Tf 

r 

t-H 

»HjC^ 

MC* 

CM 

rH 

Hr 

He* 

o 

rH 

Tj< 

can 

oo 

echr 

Hr 

CO 

t- 

■Hie* 

eoM 

CO 

HO 

Hr 

win 

co 

r 

CO 

WlH 

CO 


• 

m 

• 

03 

JO 

<33 

02 

03 

rr 

t-H 

3 

O 

r-i 

Pm 

• »—f 

• 

G 

G 


<3 

J-i 

5 

£ 


CO 

tH 

302 

rH 

oo 

CO 

CM 

He* 

rH 

T—f 

He* 

03 

O 

CM 


Hr- 

rH 

CO 

tH 

co 


rH 

ee|H 

rH 

o 

t— 

H 

lH 

Hc^ 

o 

rH 

He* 

03 

HO 


rH 

Hr 

Hr 

O 

rH 

CO 

r 


rH 


nit 

o 

I- 

rH 

CO 


rH 


HN 

05!h 

L- 

C3 

CM 


tH 


OO 

03 

rH 

rH 

H 

03 

03 

O 

H 


Hr 

03 

o 

o 


TH 

WlH 

He* 

00 

CM 

03 

He* 

Hr 

CO 

r 

co 

Hr 

Hr 

00 


!>■ 


Me* 

OO 

o 


t— 

j 

• 

• 

<33 

• 

<—’ 

m 

<33 

r 

r-» 

G 

JH 

G 


o 

.a 

PM 

a 

.a 

c3 

• 

-H> 

5 

£ 


co 

co 

CM ^ 

np ^ 

a s 


<33 

<33 

’~G 


O 

o> 

•XS 


O) « 

G JG 


JO 

MV 03 

G- 3G 

*+3 Qh 

r . • r-H 

3 ^ 

a 3 
a 

«h 

c3 _r 

Cg 

£ £ 

<u 

a ~ 

o3 G2 

3G cS 
"C! _o 

03 <p 

JO JO 


03 G 
o 1 

3 co 
o o> 


.—T o 

s .a 

o 

c 3 

2 3 

o 

•A C 4 _, 
02 ^ 
a 

« L 

§ S 

«- = 
o G 

^ 03 


02 

-3 

G 

D 

O 

Oh 


O .G 


a 

jo 

03 

JO 

+3 

CfH 

O 


bo ~ 

*55 2 


^ • i-H 

r-J > 


■o 

c 

«o 


to 

• l-J 

o 

IS 

<33 

J3 


<33 

> 


HJ 

<33 

G 
TS 
O 

<33 £h 

r* • 

rH 

































































































































TABLE 

SHOWING THE WEIGHT OF ROUND-IRON FROM 3 AN INCH TO 6 INCHES IN DIAMETER, 1 FOOT LONG. 

For Calculating the Weight of Shafting , etc. 


625 


THE ENGINEER’S HANDY-BOOK. 


—|oo 

<M 

rH 

(M 

fox 

t>|ao 

rH 

h~» 

os 

COJrf 

rH 

oo 

»c|oo 

rH 


T“< 

CO 

CO|00 

rH 

lO 

HH 

rH 

^|rf 

HOO 

H 

CO 

rH 

WfW* 

<M 

H 00 

<M 

Ml*** 

rH 

if?|cO 

rH 


W|rj- 

Diameter in Inches. 

Weight in Pounds. 


Hoo 

O 

CO 


MW 

co 

L— 

CO 

uiiao 

LO 

CO 

CO 

CO 

— 

CM 

CO 

coiao 


CO 

o 

CO 

’-I't 

QO 

CO 


—ioo 

CO 

CO 

CM 

CO 

CM 

M® 

M 

(M 

CM 

WM* 

O 

CM 

' CM 

>c(ao 

CM 

rlhT 

GO 

' rH 

CM 

«W 

CO 

r —1 

colco 

LO 

(M 

H 

’-‘W 

CM 

CO 

rH 

• 

• 

« 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

• 

go 


CD 

rn 

o 

03 

d 

WH 

d 


o 

d 

Pw 



U 


<V 


-W 

4-3 

CD 


2 

fcfi 

c 3 

CD 

• >-H 

P 

£ 



S’ 


53 


2 P 



























































































TABLE 

SHOWING THE WEIGHT OF BOILER-PLATES 1 FOOT SQUARE AND FROM AtH TO AN INCH THICK. 


626 


THE ENGINEER^ HANDY-BOOK. 


rH 

40 

«OlC0 

-let 

t- 

CO 

t-to 

lO 

co 

eolco 

^1*—* 

—let 

<M 

CO 

COlTf 

o 

CO 

-N> 

— r* 

—|e» 
t— 

CM 

- *eto 

to 

<M 

_to 

—let 

CM 

CM 


O 

<M 

r* 

-let 

1— 

tH 

cc|ao 

to 

T—1 

A© 

H 

1 

121 

—|H 

o 

rH 

„K£> 

h 

-let 

t- 

—tt> 

O 

ICD 

H 

-let 

CM 

Thick, in Ins.. 

Wt. in Lbs. | 
per ft. sq. j 


O 

o 

1-1 

H 

O 

O 

P 


W 

to 

P 

O' 

to 

to 

W 

a 

o 


— 

to 

O 


a 

o 

S5 





I 

P 

to 

« 

W 

P 

to 

P 

& 

to 

P 

O 

H 

H 

H 

O 

w 


K 

M 

H 

H 

O 


O 

a 

Mi 


—to 

CO 

CO 

CO 

CO 

-let 

O 

CO 

t-lto 

CM 

CO 

CM 

COirJ* 

CM 

-let 

t-O 

CM 

-let 

CM 

—fa* 

CO 

CM 

«5i® 

(M 

CM 

CM 

w|ao 

05 

<M 

rH 

HH 

t- 

CM 

rH 



-to 

CM 

to 

rH 



CM 

co 


rH 

t>to 

CM 

rH 

T—H 


-let 

O 

T—1 

rH 

io|ao 

rH 

05 


-let 

rH 

t- 

eoto 

—let 

tH 

CO 

HH 

—w 

rH 

to 

—to 

-In* 

1—1 



»h|?| 

rH 

CO 


H?* 

H* 

CM 


CM 

»e|oo 

HH 

rH 


lo 

-let 

°V 

. 

• 

• 

• 

* 

c« 

• 

PO 

• 


c3 

•— 

a 

a 

. r-H 

a 

■4^ 

a" 


CC 



CO 

«w 

rH 

CM 

T—l 

eoirp 

to 

tH 

T—l 

T—l 

-let 

to 

— IH 

CM 

O 

T—1 

’-IH 

LO 

— W 

CO 

05 

to 

—let 

QO 

trice 

rHIrp 

O 

GO 

M|-t 

— IH 

CO 

t- 

mto 

-let 

CM 

t- 

-let 

■H 1 

—ret 

QO 

CO 

ecto 

rr 

eei-r 

rc 

CO 

t-Trf 

rH 

CO 

—to 

—|e* 
t— 

to 


to 

r>|oo 

CO 

eehr 

O 

to 

M|Tf 

CO 

-let 

L— 

>eto 

CO 

—let 

-let 

CO 

-let 

T—1 

ceix 

CO 

—'?» 

QO 

CO 

Hrf 

CO 

eoi»r 

to 

CO 

Square. 

Wt. in Lbs.... 























































































































627 


THE ENGINEER’S HANDY-BOOK. 


TABLE 

SHOWING THE WEIGHT OF CAST-IRON PIPES, 1 FOOT IN LENGTH, FROM \ 
INCH TO 1* INCHES THICK AND FROM 3 INCHES TO 24 INCHES DIAMETER. 


o> 

(h 

pq £ 



Thickness in 

Inches. 



° G 

G t-t 

C _ 

i 

3 

8 

1 

2 

5 

8 

3 

J 

7 

8 

1 

n 

l* 

.2.2 

w 

Lbs. 

Lbs. 

Lbs. 

Lbs. 

Lbs. 

Lbs. 

Lbs. 

Lbs. 

Lbs. 

3 

81 

121 

171 

221 

27* 

• • • • • • 

•••••• 


••«••• 

3* 

91 

141 

19* 

251 

311 

•••••• 



i » • • • • 

4 

10 

161 

22 

28* 

35 

• • • • * * 

•••••• 



4* 

lit 

18 

24* 

31* 

38f 

• ••••« 




5 

13 

191 

27 

34* 

421 

50* 

59 



5* 

15 

21* 

29* 

37* 

46 

54f 

631 

• • • • • • 

•••••• 

6 


23* 

32 

401 

49f 

59 

681 

781 

881 

6? 


251 

34* 

431 

53* 

63* 

73* 

841 

95 

7 


271 

361 

461 

561 

671 

78* 

891 

1011 

7* 


29 

39 

50 

601 

72 

83* 

951 

107* 

8 


301 

411 

53 

64* 

761 

88* 

1001 

113* 

8* 


33 

44* 

561 

681 

801 

93* 

106* 

120 

9 


34* 

46* 

59 

71f 

84f 

98* 

lilt 

1251 

91 


361 

49 

62 

75* 

89 

103 

117* 

132 

10 


381 

51* 

651 

791 

93* 

108 

1221 

138 

10* 



54 

681 

821 

971 

1121 

128* 

1441 

11 



56* 

711 

86* 

102 

1171 

134 

1501 

11* 



59 

761 

90 

1061 

1221 

139* 

156* 

12 



611 

77* 

93* 

110* 

127* 

145 

162* 

13 

- 



82f 

1011 

1181 

137* 

154 

173* 

14 




891 

1081 

126* 

1461 

1651 

1851 

15 




951 

1151 

1351 

1561 

1761 

198 

16 





1231 

143 

166 

187* 

2111 

17 





1301 

152* 

178* 

1981 

223* 

18 





137 

1611 

1851 

209 

2351 

19 





•••••« 

1691 

1951 

2221 

247 

20 





•••••• 

178 

2051 

2331 

259 

21 





•••••• 

•••••• 

214 

243* 

2731 

22 





•••••• 


2231 

244t 

2851 

23 





• • • • • • 


233* 

265* 

2981 

24 




. 

. 


2451 

277* 

310* 



























































































628 


THE ENGINEER’S HANDY-BOOK. 


TABLE 


SHOWING THE STANDARD WEIGHTS OF CAST-IRON WATER-PIPE. 

3 inch, 15 lbs. per foot — 180 lbs. per length of 12 feet. 


4 inch, 22 

<< 

u 

= 264 

« 

« 

a 

u 

6 inch, 33 

u 

(( 

== 400 

u 

Ci 

u 

u 

8 inch, 42 

<< 

u 

= 500 

u 

a 

u 

(( 

10 inch, 60 

(( 

{< 

= 720 

u 

(( 


«« 

12 inch, 75 

u 

u 

= 900 

(( 

« 

«« 

a 


TABLE 


SHOWING THE STANDARD WEIGHTS OF CAST-IRON GAS-PIPE. 


3 inch, 12? lbs. per foot 

4 inch, 17 
6 inch, 30 
8 inch, 40 

10 inch, 50 
12 inch, 70 


<< 




<< 


« 


«( 


u 


« 


« 


«( 


a 


= 150 
= 204 
= 360 
= 480 
= 600 
= 840 


lbs. per length of 12 feet. 

<< a u a 

u « « u 

u u U « 

<« u « u 

<« « (< « 


TABLE 


SHOWING THE TENSILE STRENGTH OF VARIOUS QUALITIES OF AMERICAN 

CAST-IRON. 

Breaking weight of 
a square inch bar. 


Common pig-iron,.15,000 

Good common castings, ....... 20,000 

Cast-iron “. 20,834 

“ “.19,200 

“ “. 27,700 

Gun-heads, specimen from,. 24,000 

“ “ “. 39,500 

Greenwood cast-iron, ....... 21,300 

(after third melting,) . . . 45,970 

Mean of American cast-iron, . . . . . .31,829 

Gun-metal, mean, ........ 37,232 








THE ENGINEER'S HANDY-BOOK 

English Cast-Iron. 

Low Moor,. 

Clyde, No. 1,. 

Clyde, No. 3, . 

Calder, No. 1, 

Stirling, mean,. 

Mean of English, ..... 

Stirling, toughened iron, 

Carron No. 2, cold-blast, 

“ “ 2, hot-blast, .... 

“ “ 3, cold-blast, 

“ “ 3, hot-blast, .... 

Davon, No. 3, hot-blast,.... 

Buffery, No. 1, cold-blast, 

“ “1, hot-blast, 

Cold-Talon (North Wales), No. 2, cold-blast, 

“ “ “ “ 2, hot-blast, 

TABLE 


SHOWING THE TENSILE STRENGTH OF VARIOUS QUALITIES OF AMERICAN 

WROUGHT-IRON. 


From Salisbury, Conn., .... 

Breaking weight of 
a square inch bar. 

. 66,000 

Pittsfield, Mass., .... 

• • • 

57,000 

Bellefonte, Pa., .... 

• • • 

58,000 

“ Maramec, Mo., .... 

• • • 

43,000 

a u a 

• • • • 

• • • 

53,000 

“ Centre County, Pa., 

• • • 

58,400 

il Lancaster County, Pa.,. 

• it 

58,061 

“ Carp River, Lake.Superior, . 

• • • 

89,582 

“ Mountain, Mo., Charcoal bloom, . 

• • • 

90,000 

American hammered, .... 

• • • 

53,900 

Chain-iron, ...... 

• • • 

43,000 

Rivets, ....... 

• • • 

53,300 

53* 




Breaking weight of 
a square inch bar. 

. 14,076 
. 16,125 
. 23,468 
. 13,735 
. 25,764 
. 19,484 
. 28,000 
. 16,683 
. 13,505 
. 13,200 
. 17,755 
. 21,907 
. 17,466 
. 13,437 
. 18,855 
. . 16,676 
















630 


THE ENGINEER^ HANDY-BOOK. 


SoltSj « • • • • 

Boiler-plates, .... 
Average boiler-plates, 

“ joints, double-riveted, 

“ “ single “ 

Chrome steel, highest strength, 
“ lowest “ 


(t 

a u 


average 
Homogeneous metal, 

“ “ 2d quality, 

Bessemer steel, 


<< 


u 


u 


n 


Breaking weight of 
a square inch bar. 


52,250 

50,000 

55,000 

35,000 

28,600 

198,910 

163,760 

180,000 

105,732 

81,663 

148,324 

154,825 

157,881 


TABLE 

SHOWING THE RESULTS OF EXPERIMENTS MADE ON DIFFERENT BRANDS 
OF BOILER-IRON AT THE STEVENS INSTITUTE OF TECHNOLOGY, HO¬ 
BOKEN, N. J. 

Thirty-three experiments were made upon the iron taken from 
the exploded steam-boiler of the ferry-boat “Westfield.” The 
following were the results: 

Lbs. per sq. in. 

Average breaking weight, 4 . . . . 41,653 

16 experiments made upon high grades of American 
boiler-plate. 

Average breaking weight,.54,123 

15 experiments made upon high grades of American 
flange-iron. 

Average breaking weight,.42,144 

6 experiments made upon English Bessemer steel. 

Average breaking weight,. 82,621 

5 experiments made upon English Low Moor boiler-plate. 

Average breaking weight, ..... 58,984 






THE ENGINEER’S HANDY-BOOK. 


631 


Lbs. per sq. in 

6 experiments made upon samples of tank-iron taken 
from different manufacturers. 

Average breaking weight No. 1, . . . . 43,831 

“ ' “ “ No. 2, . . . . 42,011 

“ “ “ No. 3, . . . . 41,249 

2 experiments made on iron taken from the exploded 
steam-boiler of the “ Red Jacket.” 

Average breaking weight,. 49,000 

It will be noticed that the above experiments reveal a great 
variation in the strength of boiler-plate of different grades. 

TABLE 

GIVING THE PROPORTIONS OF THE UNITED STATES OR SELLERS’ STANDARD 
THREADS FOR SCREWS, NUTS, AND BOLTS. 


Outside Diameter of 
Screw in Inches. 

Number of Threads 
per Inch. 

Diameter of Screw 
at the Root of the 
Thread in Deci¬ 
mals of an Inch. 

Width of Top and 
Bottom of Thread 
in Decimals of an 
Inch. 

Outside Diameter of 
Screw in Inches. 

Number of Threads 
per Inch. 

Diameter of Screw 
at the Root of the 
Thread in Deci¬ 
mals of an Inch. 

Width of Top and 
Bottom of Thread 
in Decimals of an 
Inch. 

1 

T 

20 

•185 

•0062 

2 

41 

1-712 

•0277 

5 

1 ft 

18 

•240 

•0074 


41 

1*962 

•0277 

3 

p 

16 

*294 

•0078 

21 

4 

2*176 

•0312 


14 

•344 

*0089 

2f 

4 

2-426 

•0312 

1 

2 

13 

•400 

•0096 

3 

31 

2-629 

•0357 

9 

TA” 

12 

•454 

•0104 

31 

31 

2-879 

•0357 

5 

g 

11 

•507 

•0113 

31 

31 

3-100 

•0384 

3 

% 

10 

•620 

•0125 

3 f 

3 

3-317 

•0413 

i 

9 

•731 

•0138 

4 

3 

3*567 

•0413 

1 

8 

•837 

•0156 

41 

2f 

3-798 

•0435 

if 

7 

•940 

•0178 

41 

03 

4-028 

•0454 

H 

7 

1-065 

•0178 

41 

2f 

4-256 

•0476 

li 

6 

1*160 

•0208 

t> 

21 

4-480 

•0500 

il 

6 

1-284 

•0208 

51 

21 

4*730 

•0500 

if 

51 

1-389 

*0227 

51 

2f 

4*953 

•0526 

if 

5 

1-491 

*0250 

5f 

2§ 

5*203 

•0526 

if 

5 

! 

1-616 

•0250 

6 

21 

5-423 

•0555 



































632 


THE ENGINEER’S HANDY-BOOK. 


The “ pitch ” of a thread is the distance which it travels length¬ 
ways for one revolution of the screw. 

The thickness or depth of a nut, to give equal strength, must be 
equal to the outside diameter of the screw or bolt. 


Speed, Power, Capacity, and Press of Millstones. 


Diameter of 
Millstone. 

Revolutions 
per Minute. 

Horse-Power. 

Average Ca¬ 
pacity per 
Hour of 
Grinding in 
Bushels. 

Usual Dress. 

Draught 
from Fore 
Edge of Fur- 
row. 

Ft, 

2 

In. 

G 

200 

2-| 

24 

7*3 

Inches. 

24 

2 

10 

180 

2f 

2f 

8*2 . 

24 

3 

0 

170 

3 

3 

9-3 

91 

3 

2 

160 

34 

34 

9*3 

93 

3 

4 

150 

H 

34 

10*3 

3 

3 

6 

140 

3f 

3f 

10-3 

3 

3 

8 

130 

3| 

3 1 

10-3 

3 

3 

10 

125 

3| 

Nearly 4 

11-3 

3 

4 

0 

120 

4 

4 

10-4 

3 

4 

2 

115 

44 

44 

10-4 

3 

4 

4* 

110 

44 

44 

11-4 

34 

4 

6 

105 

4* 

5 

12-4 

34 

4 

8 

100 

4| 

6 

12*4 

3f 

4 

10 

95 

5 

64 

12-4 

4 

5 

0 

90 

6 

7 

12'4 

44 


Speed of Circular-Saws. 

About nine thousand feet per minute for the rim of a circular- 
saw to travel may be laid down as good speed: a saw twelve 
inches in diameter, 3 feet around the rim, 3,000 revolutions; 24 
inches in diameter, or 6 feet around the rim, 1,500 revolutions; 

3 feet in diameter, or 9 feet around the rim, 1,000 revolutions; 

4 feet in diameter, or 12 feet around the rim, 750 revolutions; 5 
feet in diameter, or 15 feet around the rim, 600 revolutions. 

Rule for finding the proper number of revolutions per minute of 
any sized saw .— Divide 36,000 by the diameter of the saw in 
inches; the quotient will be the right number of revolutions. 

Example. —36,000 divided by 60 equals 600, the number of 
revolutions a 60-inch saw should make. 


















633 


THE ENGINEER’S HANDY-BOOK. 


TABLE 


OF COEFFICIENTS OF FRICTIONS BETWEEN PLANE SURFACES. 


Sliding 

Surface. 

Surface at 
Rest. 

Cast-iron. 

W rought- 
iron. 

Cast-iron. 

Cast-iron. 

Wrought- 

iron. 

Bronze. 

Bronze. 

Wrought- 

iron. 

Cast-iron. 

Bronze. 

Bronze. 

Cast-iron. 

Bronze. 

Bronze. 

Brass. 

Cast-iron. 

Steel. 

<< 

Steel. 

Steel. 

W rought- 
iron. 
Bronze. 


State of the Surfaces. 


f Fibres of 1 
j both sur- j 
-J faces par- }- 
j allel to 
[_ motion. 


U 


Fibres par¬ 
allel to 
motion. 


*< 


U 


Cl 


Fibres of 
iron pa¬ 
rallel to 
motion. 


surfaces unctuous . 
without lubricant . 
surfaces unctuous . 

[ tallow 
lubricated ] lard . 
with j olive-oil 
[ lard and 
without lubricant . 
surfaces unctuous . 

lubricated f ‘“J 1 ”" 

wlth 1 olive-oil 

without lubricant . 

surfaces unctuous . 

... . i f tallow 

lubricated I Jar(J and 

Wllh (olive-oil 

without lubricant . 

surfaces unctuous . 

... . i f tallow 

lubricated krd 

Wllh (olive-oil 
without lubricant . 
surfaces unctuous . 
lubricated j tallow 
with ( olive-oil 
without lubricant . 
surfaces unctuous . 
lubricated with olive- 
without lubricant . 
surfaces unctuous . 

lubricated J 

with ] ‘ • 'm 
wu ( olive-oil 

without lubricant . 

, .if tallow 
lubricated I , ard _ 

w,th (olive-oil 
lubricated I tallow 
with ( lard . 
without lubricant . 

tallow 
olive-oil 


plbg. 


plbg 


lubricated J 


with 


oil 


| lard and pibg. 


Coeffi¬ 
cient of 
Friction. 


0-143 

0-152 

0-144 

o-ioo 

0-070 

0-064 

0*055 

0-072 

0-060 

0-103 

0*075 

0-078 

0-161 

0-166 

0-081 

0-089 

0-072 

0-147 

0-132 

0-103 

0-075 

0-078 

0-217 

0-107 

0086 

0-177 

0-201 

0-134 

0-058 

0-189 

0-115 

0-072 

0-068 

0-066 

0-202 

0-105 

0-081 

0-079 

0-093 

0-076 

0-152 

0-056 

0-053 

0-076 




























634 


THE ENGINEER’S HANDY-BOOK. 


Non-Conducting Covering for Steam-Boilers and Pipes. 


Make a thin paste by boiling flour and water, then stir in as 
much sawdust as it can hold together. After drying, it will adhere 
to iron when slightly warm, after which several coats may be 
applied in succession. It may be made water-proof by painting 
with coal-tar. 

Or, mix thoroughly equal parts of fuller’s-earth and finely-sifted 
coal-ashes ; add to the pasty mass a small quantity of calves-hair. 
Before laying it on a pipe, add 4 its quantity of calcined gypsum, 
and lay on in thin layers. The pipe or cylinder should be warm 
when the mass is applied. 

The annexed cut represents what is known to mechanics as an 
expansion-joint, such as is used on short, straight steam-pipes in- 

contracted places, for the 
purpose of preventing 
them from breaking or 
throwing the machinery 
out of line by the force 
of expansion. A shows 
the socket, or stuffing- 
box ; B , the tube or pipe; 
C, the guide employed 
for the purpose of keep¬ 
ing the pipe straight; F F, the studs by which the gland is ad¬ 
justed, and the guide, C, retained in position ; a a is the cavity 
which contains the fibrous packing for the purpose of preventing 
leakage; e e, the recess into which the head, D, is drawn when the 
pipe contracts; and G the female tube into which it is forced 
by expansion. 



Steam-Joints. 


Cement for steam-joints and patching steam-boilers. — Take 
any desired quantity of pure red lead, put it in an iron mortar, on 
a block or thick plate of iron. Put in a quantity of white lead 
ground in oil; knead them until you make a thick putty; then 
pound it; the more it is pounded the softer it will become. Roll 












































THE ENGINEER’S HANDY-BOOK. 635 

4 

in red lead, and pound again; repeat this operation of adding red 
lead and pounding, until the mass becomes a stiff putty. In ap¬ 
plying it to the flange or joint, it is well to put a thin grummet 
around the orifice of the pipe, to prevent the cement being forced 
inward to the pipe when the bolts are screwed up. When the 
flanges are not faced, make the above mass rather soft, and add 
cast-iron borings run through a fine sieve, when it will be found 
to resist either fire or water. 

Or, powdered litharge, 2 parts; very fine sand, 2 parts ; slaked 
quicklime, 1 part. Mix all together. So use. Mix the proper 
quantity with boiled linseed-oil, and apply quickly. It gets hard 
very soon. 

Or, white lead ground in oil, 10 parts; black oxide of manga¬ 
nese, 3 parts; litharge, 1 part. Reduce to the proper consistency 
with boiled linseed-oil, and apply. 

Or, red lead ground in oil, 6 parts; white lead, 3 parts; oxide 
of manganese, 2 parts; silicate of soda, 1 part; litharge, I part; 
all mixed and used as putty. 

Or, take 10 pounds of ground litharge ; 4 lbs. of ground Paris 
white; \ pound of yellow ochre and i oz. of hemp; cut into 
lengths of i inch; mix all together with boiled linseed-oil to the 
consistency of a stiff putty. This cement resists fire and will set 
in water. 

Cement for rust-joints. — Cast-iron borings or turnings, 19 
lbs.; pulverized sal-ammoniac, 1 pound ; flour of sulphur, § pound. 
It should be thoroughly mixed, and passed through a tolerably 
fine sieve. Sufficient water should be added to wet the mixture 
through. It should be prepared some hours before use. A small 
quantity of sludge from the trough of a grindstone will improve 
its quality. ^ 

All movable joints of the best description of land- and marine- 
engines are now faced on a lathe or planer, and then rendered 
perfectly steam-, air-, and water-tight by filing and scraping, so 
that all that is necessary, when put together, is to oil their sur¬ 
faces. 



636 


THE ENGINEER’S HANDY-BOOK. 


Fop smooth surfaces that can be conveniently calked, sheet- 
copper, annealed by heating to a cherry red and then plunging it 
into cold water, makes a permanent joint. 

Lead-wire makes a very cheap, clean, and permanent joint. 
Copper-wire also makes a good joint; but, when convenient, it is 
always best to plane or turn a groove in one of the surfaces to be 
brought into contact. 

For uniform surfaces, gauze wire-cloth coated on either side 
with white or red lead paint makes a very durable joint, particu¬ 
larly where it is exposed to high temperatures. 

For pumps or stand-pipes in the holds of vessels, canvas well 
saturated on both sides with white or red lead makes a very dur¬ 
able joint. Pasteboard painted on both sides with white or red 
lead paint is frequently used with good results. 

How to make a good adhesive cement. — Mix pulverized 
gum-Arabic with its weight of finely-powdered calcined alum. 
When mixed with a small quantity of water, it forms a cement 
which unites wood, paper, porcelain, glass, and crockery very firmly. 
It must be kept dry in powder and moistened only as needed. 

A cement for leather may be made by dissolving in a mixture 
of ten parts of bi-sulphide of carbon and one part of oil of turpen¬ 
tine enough gutta-percha to thicken the composition. The leather 
must be freed from grease, which may be done by placing a cloth 
between the leather and a hot iron. The pieces cemented must be 
pressed together until the cement is dry. 

A cement for fastening leather to iron, china, or glass. — To 
one quart of glue dissolved in good cider vinegar add one ounce 
of good Venice turpentine. It should be allowed to simmer about 
half a day. 

Cement for leather belting. — Of common glue and American 
isinglass, take equal parts; place in a kettle, and add sufficient 
water to cover the whole. Let them soak ten hours ; then bring 
the mixture to the boiling point, and add pure tannin, until the 
whole becomes ropy, or appears like the white of eggs. Apply it 
warm. Buff the grain off the leather where it is to be cemented; 



THE ENGINEER'S HANDY-BOOK. 637 

rub the joiut surfaces solidly together, and let it dry for a few 
hours. 

Cement for rubber belting. — Take 16 parts of gutta-percha 
or India-rubber; 2 parts common pitch; and 1 part linseed- 
oil. Melt together, and use hot. This cement will unite leather 
or rubber that has not been vulcanized. 

Cement for brass and glass. — Boil 3 parts of resin with 1 
part of caustic soda and 5 of water. Add five times its weight 
of plaster of Paris. It sets firmly in from half- to three-quarters 
of an hour. Zinc, white lead, or precipitated chalk may be sub¬ 
stituted for plaster, but hardens more slowly. 

Cement for stone or marble. —The best cement for mending 
marble, or any kind of stone, is made by mixing 20 parts of lith¬ 
arge and 1 part of freshly-burned lime in fine, dry powder. This 
is made into a putty by the addition of linseed-oil. It sets in a 
few hours, having the appearance of light stone. 

Belting. 

While the use of belts for the transmission of power is not an 
American invention, the numerous improvements made in this 
country have caused it to be known in Europe as the American 
system. In Europe the greater part of the power is transmitted 
by cog-wheels, but in this country 99 per cent, is transmitted by 
belting. The latter is used everywhere, from the sewing-machine 
to the 500 horse-power engine of the largest factory. 

Belts can be run in any way, at any angle, of any length, and 
at any speed, and can be put up by any one of ordinary skill. 
They can be made of any flexible material — leather, rubber, 
gutta-percha, or cloth ; yet, while so hardy and so popular, they 
have one fault — they are not positive. If the motion makes a 
certain number of revolutions, a portion of them is lost with 
every belt used. This is the only fault of the system. It is noise¬ 
less, yielding, and regular; but, unlike cog-wheels, it is not posi- 
54 



638 


THE ENGINEER’S HANDY-BOOK. 


tive. The number of revolutions that are lost may, and do, vary 
continually by changes of the load or of the atmosphere. 

Belts derive their power to transmit motion from the friction 
between the surface of the belt and the pulley, and from nothing 
else, and are governed by the same laws as in friction between flat 
surfaces. The friction increases regularly with the pressure. The 
great difference often observed in the friction of belts is due simply 
to their elasticity of surface; that is, the more elastic the surface 
the greater the friction. 

In taking power from any source of motion, there are two points 
which control us; all the others we can control and modify to a 
certain extent. Ordinary belts will sustain safely a working ten¬ 
sion of 45 lbs. per inch in width; the rule to determine the width 
of belt and size of pulley required to transmit a given horse-power 
is easily found. Since a horse-power is 33,000 pounds raised one 
foot high per minute, we must adjust the width and velocity of 
belts so as to effect the required result. Thus, if the belt moves 
with a velocity of 733 feet per minute, a belt five inches wide 
will transmit five horse-power, provided the effective tension is 45 
lbs. per inch. If the velocity be increased to 1466 feet per min¬ 
ute, the same belt with the same tension will transmit ten horse¬ 
power. So that a five-inch belt, applied to a five-foot pulley mak¬ 
ing 120 revolutions per minute, would transmit ten horse-power 
when the effective tension is 225 pounds. 

By taking the actual effective tension of the belt, and multiply¬ 
ing it by the actual velocity, we get what may be called the in¬ 
dicated horse-power of the belt, which corresponds to the indicated 
horse-power of the engine. And, finally, by measuring the act¬ 
ual power transmitted — which may be done by means of a dyn¬ 
amometer — we can get the actual power transmitted. Rules 
based upon the amount of belt surface in contact with the pulley, 
and on similar data, cannot be made to give reliable results. For 
practical purposes, velocity and power to resist tension are the 
only available elements of the calculation. Actual tension, adhe¬ 
sion, friction, etc., can all be varied at will, and consequently form 


THE ENGINEER^ HANDY-BOOK. 639 

no certain dependence for the calculations of the machinist and 
engineer. 

On the scientific principle that the adhesion, and consequently 
the capability of leather belts to transmit power from motors to 
machines, is in proportion to the pressure of the actual weight of 
the leather on the surface of the pulley, it is manifest that, as 
longer belts have more weight than shorter ones, and that broader 
belts of the same length have more weight than narrower ones, it 
may be adopted as a rule that the adhesion and capability of belts 
to transmit power are in the ratio of their relative lengths and 
breadth. A belt of double the length or breadth of another 
under the same circumstances, will transmit more than double the 
power. For this reason it is desirable to use long belts. By 
doubling the velocity of the same belt, its effectual capability for 
transmitting power is also doubled. 

Good stock is the first requirement of a belt, which, if spongy, 
will not meet that demand. It must be firm, but pliable; the 
grain or hair side should be free from wrinkles; the stock should 
show no irregularities in dressing, but be of an even thickness 
throughout; the splices should be mathematically true, and if 
rivets are employed, they should be inserted on the hair side, and 
the burrs sent home before riveting; the edges should be parallel 
and perfectly straight. In handling a belt, examine it carefully, 
double it up, the hair side out, and press it together; if it crack 
under this treatment, it should be rejected, as the rational use of a 
belt consists in utilizing the whole amount of power it will trans¬ 
mit. 

Belts are sometimes used having a transmitting power of double 
the capacity necessary where they are employed, while ‘quite as 
often they are much too narrow for the work required of them. 
The first instance shows a useless waste of material, the latter 
poor economy; as, in order that it may perform the work required, 
it is necessary frequently to take it up, as a result of which the 
weak points succumb to the strain, and it is torn asunder; or if 
not, the shaft is likely to be drawn out of line, or the bearing over¬ 
heated. 






640 


THE ENGINEER’S HANDY-BOOK. 


In using a new belt a few days, if it present a mottled appear¬ 
ance on the side next to the pulleys, it may be set down that it is 
not furnishing the full capacity of its power. The spots referred 
to indicate that certain portions of the belt do not touch the 
pulley, and that its entire transmitting power is not utilized. If 
the face of the pulley is true, and the belt is as nearly perfect as 
possible, the defect may be remedied by the judicious application 
of rendered tallow and fish oil, two parts of tallow to one of oil, 
melted and allowed to cool. A new belt should be used a day or 
two before it is oiled, and frequent application of small quantities 
are better than too liberal oiling at long intervals. 

If a belt, of the proper size for the work it has to do, slip on the 
pulley, it is caused by the centrifugal force, which tends to throw 
it outward; a corresponding degree of tension will check the 
defect. 

Belts should be put on by a person acquainted with their use, 
as the wear of the belt depends considerably on the manner in 
which it is put on; therefore, the following suggestions, if prac¬ 
tised, will be of much service to persons employed in this capac¬ 
ity. The ends to be joined should be cut perfectly square, in 
order that one side may not be drawn tighter than the other. 
Good lace-leather, if properly used, will give better satisfaction 
than any patent fastening. 

Where belts run vertically, they should always be drawn moder¬ 
ately tight, or the weight of the belt will not allow it to adhere 
closely to the lower pulley; but in all other cases they should be 
slack. In many instances, the tearing out of lace-holes is unjustly 
attributed to poor belting; when, in reality, the fault lies in having 
a belt too short, and trying to force it together by lacing, and the 
more the leather has stretched while being manufactured, the more 
liable it is to be complained of. 

To obtain the greatest amount of power from belts, the pulleys 

should be covered with leather. This will allow the belts to be 
run very slack, and give 25 per cent, more wear. 

More power can be obtained from using the grain side of a belt 


THE ENGINEER^ HANDY-BOOK. 


641 


to the pulley thau from the flesh side, as the belt adheres more 
closely to the pulley; but it should be remembered that the belt 
will not last quite so long, as when the grain, which is very thin, 
is worn off, the substance of the belt is gone. 

Double-leather belts are frequently used; but it is clearly a 
mistake, as a single-leather one will transmit more of the power 
than a double one. Double-leather belts run straighter thau single 
ones, as the flank side of one part can be put against the back 
of the others. A double belt will stand a greater tension than a 
single one, but a single belt will stand all that should be put upon 
any belt. 

In cases where a belt is incapable of transmitting the required 
amount of power, and circumstances preclude the possibility of 
substituting a wider one, the difficulty may be overcome by using 
two belts of the same width, one on the top of the other. Two 
belts run in this way will transmit nearly as much power as one 
belt the width of the two. 

How to test the quality of leather for belting. — Cut a small 
strip of the leather about T 'g of an inch in thickness, and place it 
in strong vinegar. If the leather has been thoroughly tanned, 
and is of good quality, it will remain for months even immersed, 
without alteration, simply becoming a little darker in color. But, 
on the contrary, if not thoroughly tanned, the fibres will quickly 
swell, and, after a short period, become transformed into a gela¬ 
tinous mass. 

How to make belts run on the centre of pulleys. —It is a com¬ 
mon occurrence for belts to run on one side of the pulleys. This 
arises from one or two causes: 1st, One or both of the pulleys 
may be conical, and, of course, the belt will run on the higher 
side. The most effectual remedy for this will be to straighten 
the face of the pulleys. 2d, The shafts may not be parallel or 
exactly in line. In this case the belt will incline off to the side 
where the ends of the shafts come the nearest together. The rem¬ 
edy in this case would be to slack up on the hanger-bolts, and 
drive the hangers out or in, as the case may be, until both ends of 
54* 2 Q 






642 the engineer’s handy-book. 

the shafts become exactly parallel. This can be determined by 
getting the centres of the shafts at both ends by means of a long 
lath or light strip of board. 

Tighteners. — The tightener should be placed as close to the 
large or driving-pulley as circumstances will permit, as the loss 
of power incurred by the use of the tightener is equal to that re¬ 
quired to bend the belt and carry the tightening-pulley. Conse¬ 
quently, there is a greater loss of power by placing it near the 
small pulley, as the belt is required to be bent more than when it 
is placed near the large one. 

The reason why belts run to the highest side of a pulley is due, 
in part, to centrifugal force, and also to the fact that the part of 
a belt nearest the highest part of a rounded pulley is more rap¬ 
idly drawn, because the circumference of the pulley is greater at 
that point. 

Rubber and leather belts. —Rubber belts will transmit nearly 
as much power as leather belts with the same tension; and they 
have this advantage, that they may be made of any length, width, 
or thickness, and yet always run straight, providing the pulleys 
are in line. Besides, their first cost is much less than those of 

i 

leather; but they will not last over half as long. They cannot 
be run in situations where the belt rubs, nor as cross-belts, or 
through forks, as shifting-belts; and when they give out, it is 
almost impossible to repair them. 

If a rubber belt runs off, and becomes entangled in the machin¬ 
ery, ten chances to one it will be completely ruined; whereas, a 
leather belt, under like circumstances, will sustain very little 
injury. When saturated with oil, they soon rot, and when situa¬ 
ted in cold, damp places, they are liable to freeze, which has a 
tendency to separate the different thicknesses and ruin the belt. 
Besides, they often freeze to the face of pulleys when standing 
still, and when started up, the gum facing is torn off, which ruins 
the belt. 

A leather belt, if made of good stock, not overstrained and 
properly treated, will last for twenty years. When partly worn 


THE ENGINEER’S HANDY-BOOK. 


643 


out, it may be cut up and used over again for a narrower or 
shorter belt; and when entirely unfit for the transmission of power, 
it may be used for different purposes around a factory; but when 
rubber belts are worn out, they are of no value whatever. 

To prevent accidents by shafts revolving within reach of opera¬ 
tives' garments in mills and factories .— Cover the shaft with a loose 
sleeve of sheet-tin or zinc, and insert a ring of thick gum or leather 
at each end, to prevent rattling. Should it become entangled with 
the garments of any of the operatives, the resistance will cause 
the sleeve to stand still while the shaft is rotating within it, by 
which the person may be extricated and accident averted. 

Rule for finding the length of belt wanted .—Add the diameter of 
the two pulleys together ; divide the sum by 2, and multiply the 
quotient by 31. Add the product to twice the distance between 
the centres of the shafts, and the sum will be the length required. 

Another rule for finding the length of a belt .—Add the diam¬ 
eter of the two pulleys together, multiply by 34, divide the pro¬ 
duct by 2, add the quotient to twice the distance between the cen¬ 
tres of the shafts, and you have the length required. 

Rule /or finding the width of belt to transmit a given horse-power. 
— Multiply 36,000 by the number of horse-power; multiply the 
speed of the belt in feet per minute by one-half the length in 
inches of belt in contact with smaller pulley; divide the first 
product by the second; the quotient will be the required width 
in inches. 

Rule for calculating the number of horse-powers a belt will trans¬ 
mit , its velocity, and the number of square inches in contact with the 
smaller pulley being given .— Divide the number of square inches 
in contact with the pulley by 2 ; multiply this quotient by the 
velocity of the belt in feet per minute, and divide by 36,000. 
The quotient is the number of horse-powers the belt will transmit. 

Another rule. —Divide the number of square inches of belt in 
contact with the pulley by 2; multiply this quotient by the ve¬ 
locity of the belt in feet per minute ; divide this amount by 32,000, 
and the quotient will be the number of horse-power. 





644 


THE ENGINEER^ HANDY-BOOK. 

Rule for finding the change required in the length of a belt when 
one of the pulleys on which it runs is changed for one of a different 
size. —Take three times the difference between the diameters of 
the pulleys and divide by 2. The result will be the length of 
belt to cut out or put in. 

How to measure a coil of belting. —Add the diameter of the 
hole, in inches, to the outside diameter of the roll; multiply by 
the number of coils in the roll; then multiply this by the decimal 
T309, and the product will be the number of feet in the roll. To 
have the exact length, the average diameter must be used if the 
roll is not perfectly round, and fractional parts of an inch must 
not be omitted in the calculation. 

How to put on a belt. —Never place a belt on the pulley in 
motion ; always place it first on the loose pulley or the pulley at 
rest; then run it on the pulley in motion. If the belt is very 
heavy, and the pulleys run at a very high speed, it is advisable to 
slack on the speed of the engine; but when this is impracticable 
or inconvenient, care must be taken to mount the belt on the exact 
face. The person engaged in so doing must have a firm footing, 
and prevent his clothing from getting in contact either with the 
belt or pulley. Where the belt is heavy, and the location such 
that it is impossible to get a solid footing and exert strength in 
running on the belt, it is best to stop the engine and mount the 
belt on the pulley as far as possible. Then take a small rope, 
double it, slip one end through the arms and around the belt and 
rim of the pulley, and the other end through the loop formed by 
the double of the rope; then stand on the floor on the opposite 
side, and draw on the rope, when the belt will be hugged to the 
periphery of the pulley. When motion is communicated, it may 
be slipped on without any trouble, while by letting go the end of 
the rope when the belt is on the pulley, the noose will be undone 
and the rope thrown off. 

Rule for finding the required size of a driving-pulley for any re¬ 
quired speed. — Multiply the diameter of the driven pulley by the 
number of revolutions it should make, and divide the product by 


THE ENGINEER^ IIANDY-BOOK. 


645 


the revolutions of the driver. The quotient will be the required 
size of driver. 

Rule for finding the diameter of a driven pidley for a given 
number of revolutions , the diameter and revolutions of the driver 
being known. — Multiply the diameter of the driver by its num¬ 
ber of revolutions, and divide the product by the number of 
revolutions of the driven pulley. The quotient will give the 
proper size of the driven pulley. 

Gearing. 

Rule for finding the diameter of toothed wheels. — Multiply the 
number of teeth by the number of thirty-seconds of an inch con¬ 
tained in the pitch, the product will be the diameter in inches and 
hundredths of an inch ; or, multiply the number of teeth by the 
true pitch, and the product by *3184. These results give only the 
diameter between the pitch-line, on one side, and the same line on 
the other side, and not the entire diameter from point to point of 
teeth on opposite sides. It must also be borne in mind that these 
results are only approximate diameters, since the wheel often varies 
from the computed diameter in consequence of shrinkage and other 
causes. 

Rule for finding the required number of teeth in a pinion to have 
any given velocity. — Multiply the velocity or number of revolutions 
of the driver by its number of teeth or its diameter, and divide 
the product by the desired number of revolutions of the pinion or 
driven. 

Rule for finding the diameter of a pinion, when the diameter of 
the driver and the number of teeth in driver and pinion are given .— 
Multiply the diameter of the driver by the number of teeth in the 
pinion, and divide the product by the number of teeth in the driver, 
and the quotient will be the diameter of pinion. 

Rule for finding the number of revolutions of a pinion or driven , 
when the number of revolutions of driver and the diameter or the 
number of teeth of driver and driven are given. — Multiply the 





646 


THE ENGINEER’S HANDY-BOOK. 


number of revolutions of driver by its number of teeth or its 
diameter, and divide the product by the number of teeth or the 
diameter of the driven. 

Rule for finding the number of revolutions of a driver, when the 
revolutions of driven and teeth, or diameter of driver and driven, are 
given. — Multiply the number of teeth or the diameter of driven 
by its revolutions, and divide the product by the number of teeth 
or the diameter of driver. 

Rule for finding the number of revolutions of the last wheel at the 
end of a train of spur-wheels, all of which are in a line, and mesh 
into one another, when the revolutions of the first wheel, and the 
number of teeth, or the diameter of the first and last are given. — 
Multiply the revolutions of first wheel by its number of teeth or 
its diameter, and divide the product by the number of teeth or 
the diameter of the last wheel; the result is its number of revo¬ 
lutions. 

Rule for finding the number of revolutions in each wheel for a train 
of spur-wheels, each to have a given velocity. — Multiply the number 
of revolutions of the driving-wheel by its number of teeth, and 
divide the product by the number of revolutions each wheel is to 
make. The result will be the number of teeth required for 
each. 

Rule for finding the number of revolutions of the last wheel in a 
train of wheels and pinions, sp>urs or bevels, when the revolutions of 
the first or driver, and the diameter, the teeth or the circumference of 
all the drivers and pinions, are given. — Multiply the diameter, the 
circumference, or the number of teeth of all the driving-wheels 
together, and this continued product by the number of revolutions 
of the first wheel; and divide this product by the continued prod¬ 
uct of the diameter, the circumference, or the number of teeth of 
all the pinions, and the quotient will be the number of revolutions 
of the last wheel. 




Back View of the Fitchburg Automatic Cut-Off Engine. 

































































































































































































































648 


THE ENGINEER’S HANDY-BO OR. 

Fitchburg Steam-Engine Company’s Automatic Cut-Off 

Engine. 

The cut on page 647 represents the Fitchburg horizontal, auto¬ 
matic, cut-off engine, with positive valve-gear and independent 
steam and exhaust arrangements. As will be observed, the frame 
is of the girder pattern, faced up at one end to receive the cylin¬ 
der and the other the pillow-block. The legs, which support the 
cylinder and main-bearing, are bolted to foundation-plates, which 
prevents the possibility of any movement. The steam-valves 
receive their motion from a movable eccentric, with variable 
throw, and admits or cuts off the steam at any desired point in 
the stroke, to meet the requirements of load and pressure. The 
exhaust-valves are worked by a direct movement from an eccen¬ 
tric keyed on the shaft. 

The governor, a cut of which may be seen on page 649, is 
placed on the main shaft, is enclosed in a disc, and is the same in 
principle, though differing somewhat in mechanism from that used 
on the Buckeye engine. It is claimed to be very sensitive and 
powerful, thus ensuring a steady motion under the most varying 
loads and steam-pressures, which is, of itself, a desideratum of 
great importance, as any increase in speed over that at which the 
engine was intended to run, is a waste of steam, and consequently 
a waste of fuel; and as any lagging of an engine behind the 
regular speed at times induces a loss of production. Because, it 
is well known that to produce economical results, the valve-gear 
must be so arranged as to admit the necessary volume of steam to 
the cylinder at the right time, and no more. 

SS is a disc which is firmly keyed to the shaft. X shows 
the position of the crank-pin in its relation to the other parts; 
A A are weights attached to arms having their fulcra at 0 0; 
HH are coiled springs, attached at one end to the arms at 0 0 
by means of swivels, and at the other by means of adjustable hooks, 
KK. As will be observed, short stub, connecting-rods, having 
one end attached to the weighted arms and the other end to the 


the engineer’s handy-book. 


649 


cast-iron collar, B, which is accurately fitted to the shaft, are 
introduced between the weights and the springs. This collar, B, 
has an arm which extends from one side to the periphery of the 
disc, and which ends in a flat weight, G , to which weights of the 



same shape may be attached. On the opposite side an ear, I, is 
shaped to receive a sliding-block; close to the periphery of the 
disc, SS, is pivoted an arm, E, its other end encircling the shaft, 
and which (in consequence of having an oblong slot) admits 
of a swinging motion across the shaft; at its end opposite the 
pivot, beyond the part encircling the shaft, is an ear or boss sus¬ 
taining a steel pin, upon which pin turns the sliding-block which 
moves in the ear, I. Upon the arm, F, is bolted the eccentric, 
which has a sufficient advance to give a f cut-off when the gov¬ 
ernor is at rest. The spottings, PP, are intended for the fulcra 
55 




























650 


THE ENGINEER’S HANDY-BOOK. 


of the weighted arms, in case it should be necessary to run the en¬ 
gine in the opposite direction. 

The action of the governor may be explained as follows :— 
When the engine is travelling below speed, the eccentric is kept in 
full throw by the tension of the spiral springs, and the steam fol¬ 
lows the piston three-fourths of the stroke. As soon as the proper 
speed is attained, the centrifugal action of the weights, A A, over¬ 
come the tension of the springs, and they move outwards in the 
direction of the arrows, thus lengthening the spring. By means 
of the connecting-rods, C C, the outward motion of the weights 
gives a motion round the shaft to the collar, B, which in turn, by 
means of the ear, G, and the sliding-block attached to the arm, E, 
gives the latter an oscillating movement from its point of suspen¬ 
sion across the shaft (as shown by the arrows), and at the same 
time to the eccentric, which is bolted to it. 

The Improved Circulating Salinometer. 

The cut on page 651 represents the Circulating Salinometer, 

the object of which is to prevent the sputtering or boiling of the 
water when drawn off from the boiler under pressure, and the 
consequent inconvenience and danger of scalding. This object is 
accomplished by reducing the temperature below the boiling-point 
before it enters the testing-pot. It serves also to keep up a con¬ 
tinuous circulation, so that the degree of saturation can be ob¬ 
served at any moment, thus avoiding the necessity of frequently 
drawing off the water, and saving the time which would be 
wasted in so doing. This salinometer consists of a large and 
small pot attached to the same bottom, one inside of the other, 
with a coil in the annular space between the two pots. This coil 
is connected at the top with a globe-valve, and at the bottom with 
a passage leading into the small or testing-cup, which contains a 
hydrometer and thermometer, the latter being hung by a spring 
hook on the upper edge of the pot. The right-hand globe-valve 
is used for admitting cold water into the annular space between 


the engineer’s handy- bo ok. 


651 


the pots, for the purpose of reducing the temperature of the 
in its passage from the boiler to the 
required degree, so that it may rise in 
the testing-pot perfectly quiescent, and 
is kept at the proper height; and the 
circulation is maintained by openings 
to the pot near the top, through which 
it overflows into the annular space be¬ 
tween the two pots, after which it es¬ 
capes with the cold water by the escape- 
pipe through the passage-way, making 
but one connection at the bottom. 

These passages are situated upon each 
side, right and left, and, should they 
become choked by sediment resulting 
from muddy water, they can be cleaned 
out by disconnecting the escape-pipe 
and running a wire through them. 

The plug-cock at the bottom is only 
used for emptying the testing-pot when 
required, and has no communication 
with anything else. 

The water from the boiler and the 
cold water can in no way become 
mixed except by the bursting of the 
coil, which is not likely to happen un¬ 
less it should be left full of water and 
allowed to freeze. The coils are thor- 
oughly tested before they are put in; 
the top is not specially designed to be. 
tight, as nothing can escape from the 
joints but the cold water, and that 
only when the annular space is allowed 
to become full, which is unnecessary, 
as a very small quantity of cold water 


water 

































































































THE ENGINEER’S HANDY-BOOK. 


will be sufficient to reduce the temperature of the water passing 

through the coil. A hole is drilled in 
the back of the large pot, near the 
top, which allows the water to escape 
in case it should accidentally become 
full. The cold water is supplied by a 
pipe connected by a globe-valve to any 
pipe or valve below the water-line sup¬ 
plying cold water, and led to the sali- 
nometer. If it should be desired to 
place the salinometer above the out¬ 
side water-level, the cold water can be 
supplied by some of the pumps. 

In erecting these salinometers, they 
may be secured to the boilers or bulk¬ 
head, but when there are two or more 
boilers, a very neat and convenient 
arrangement may be made by fitting 
them close together on a plain cast-iron 
plate fastened down with tap-bolts, and 
with the pipe for the cold water fitted 
just above them, with a T coupling 
and branch to each one, the plate being 
secured with tap-bolts in any conven¬ 
ient place in the engine-room. A 
salinometer may be attached to each 
boiler, and all of them supplied with 
cold water from the same pipe, or one 
may be connected with two or more 
.boilers. 

It is preferable to have one con¬ 
nected with each boiler, as in that case 
the density of the water may be ob¬ 
served in any boiler independent of 
the others. To put the salinometer in 




























































653 . 


THE ENGINEER’S HANDY-BOOK. 

operation, it is only necessary to open the valve communicating 
between the boiler and the salinometer, and admit the water as 
fast as the overflow will allow it to escape, and when the temper¬ 
ature reaches the required degree, the communication may be suf¬ 
ficiently closed only to allow the necessary circulation. Then the 
cold-water valve may be opened, and, if the connection with the 
boiler has considerable length of pipe to retain cold water, the 
blow-off cock may be opened to admit of its escape, and then 
closed. A very slight opening of either valve will be sufficient 
to keep up the circulation and keep the water at the required 
temperature. If the water should be admitted too rapidly from 
under pressure, the agitation of the water at the bottom, even 
below the boiling-point, will disturb the hydrometer. When the 
circulation and temperature are properly adjusted, it will not re¬ 
quire to be touched from one end of a passage to another, unless 
it may be to adjust the cold-water valve occasionally if any con¬ 
siderable change takes place in the temperature of the water in 
the boiler. 

The manipulation and operation of these salinometers are very 
simple and satisfactory, as they are a decided improvement on any 
other arrangement of the kind ever heretofore used for the same 
purpose, as, with one of them attached to each boiler, the density 
of the water may be accurately determined at any moment, which 
is a feature of great importance in many respects, aud a fact 
which will be appreciated by those who have used other arrange¬ 
ments. The different parts of the salinometer are designated as 
follows: A, hot-water pot; K , outlet for hot-water overflow; 
cold-water reservoir; H, general outlet; C, hot-water inlet to 
coil; e, outlet passage from hot-water pot; D, cold-water inlet; /, 
small pot for hydrometer; I, passage from coil to hot-water pot; 
F, outlet for cold water. 

These salinometers are manufactured by the Crosby Steam 
Gauge and Valve Company, Boston, Mass. 

55 * 






654 


THE ENGINEER’S HANDY-BOOK. 



Crosby’s Adjustable “Pop” Safety-Valve. 

The annexed cut represents Crosby’s Adjustable “Pop” 
Safety-Valve. —Its mechanism may be explained as follows: The 
valve proper, B B , rests upon two flat annular seats, V V and 

W W, on the same plane, and is 
held down against the pressure 
of steam by the steel spiral spring, 
S. The tension of this spring is 
caused by screwing down the 
threaded bolt, L, at the top of 
the cylinder, K. The area con¬ 
tained between the seats, W and 
V , is what the steam-pressure acts 
upon, ordinarily, to overcome the 
resistance of the spring. The 
area contained within the smaller 
seat, W W f is not acted upon at 
all until the valve opens. The 
large seat, V V, is formed on the 
upper edge of the shell or body 
of the valve, A A. The small 
seat, W W, is formed on the up¬ 
per edge of a cylindrical cham¬ 
ber or well, C C, which is situated 
in the centre of the shell or body 
of the valve, and is held in its 
place by four arras, D D , radiat¬ 
ing horizontally at right angles 
to each other, and connecting it 
with the body or shell of the 
valve. These arms are hollow 
and form four passages, E E, for 
the escape of the steam or other fluid from the well into the air 
when the valve is open. This well is deepened, so as to allow the 











































































































wings, XX, of the valve proper to project down into it far enough 
to act as guides. The area of the apertures at the outer ends of 
the passages through the arms is reduced more or less at will by 
screwing up or down the adjustable ring, G G. 

Action of the “Pop” Safety-Valve when under Pressure.— 
When the pressure under the valve is within about one pound of the 
maximum pressure required, the valve will open slightly, and the 
steam will escape under the larger seat into the cylinder surround¬ 
ing the spring, and thence into the air. The steam is also forced 
under the smaller seat into the well, and thence, through the pas¬ 
sages in the arms, into the air. As soon as the pressure attains 
the exact maximum point, the valve will be lifted so high as to 
force the steam into the well faster than it can escape through the 
apertures in the arms. A pressure will then accumulate under 
the inner seat, which will be in excess of what was required to 
overcome the increasing resistance offered by the spring, and, act¬ 
ing upon the additional area presented, at once forces the valve 
wide open, and rapidly relieves the boiler. This pressure under 
the inner seat is of itself differential. The valve then at once 
slowly settles down, and the pressure under the inner seat as 
slowly diminishes. This action continues until the area of the 
opening under the smaller or inner seat is less than the area of 
the apertures in the arms for the escape of the steam; the pressure 
then ceases and the valve promptly closes. The point of opening 
can be readily changed while under steam by screwing the threaded 
bolt at the top of the cylinder either up or down, and the point 
of closing is as easily adjusted by screwing up or down the ring 
surrounding the outside body or shell of the valve. 

This valve is automatic, certain in its action, prompt in open¬ 
ing and closing at the required points of pressure, and can be fully 
relied upon to relieve the boiler under all circumstances. Expe¬ 
rience and use have confirmed the following claims for it, namely, 
opens precisely at fixed working pressure; discharges all excess 
of steam above fixed working pressure; reduces the pressure rap¬ 
idly upon opening; closes with the least possible loss of steam; 





656 


THE ENGINEER’S HANDY-BOOK. 

the limits of pressure within which the valve will open and close 
are adjustable; uniform in action at different pressures; simple in 
arrangement, and easily connected and adjusted; does not deteri¬ 
orate under continued use; never sticks on seat; makes compara¬ 
tively little noise in discharging; occupies less room than any 
safety-valve. These valves are made to correspond with the re¬ 
quirements of, and are used on, locomotive, portable, steamboat, 
stationary, and steam fire-engine boilers, and for other pur¬ 
poses. Each of these valves is tested under steam pressure, and 
set to open at the exact point of pressure desired, and is ad¬ 
justed to close at about two pounds reduction. Both of these 
points may be readily changed by the operator without removing 
the valve from the boiler or reducing steam. Any person of ordi¬ 
nary intelligence will readily understand the principle and opera¬ 
tion of these valves. 



The Improved Planimeter. 

The above cut represents the improved Planimeter as espe¬ 
cially adapted for ascertaining, from the indicator diagram, the 
average pressure in the steam-engine cylinder, and also for meas¬ 
uring the superficial contents of regular or irregular plain sur¬ 
faces. It is claimed to have the advantages over any other in use, 
in being supplied with a supplementary wheel, with a graduated 
plate, marked with figures representing ten times the value of the 
figure on the roller-wheel, thus saving the care and trouble inci¬ 
dental to the use of the other single-wheel instruments, and in giv¬ 
ing the average height of the indicator diagram in one-fortieth of 



THE ENGINEER’S HANDY-BOOK. 


657 


an inch (instead of the area), which, multiplied by a factor repre¬ 
senting the scale or number of the spring used, gives the average 
pressure in pounds, without the long process and troupe of meas¬ 
uring the length of the diagram, dividing it into the area, and 
then multiplying by the vertical scale. 

It is also adapted for measuring the superficial contents of reg¬ 
ular or irregular plain surfaces, and representing the contents 
either in millimeters, inches, feet, perches, or acres, as the opera¬ 
tor may desire, by adjusting the sliding-bar. In the case of indi¬ 
cator diagrams, if the Crosby Indicator be used, the process of 
finding the area of the diagram is simplified, as the springs used 
are of such scales (mostly multiples of four) that, instead of the 
long process formerly used, the mean pressure is obtained by sim¬ 
ply multiplying by a factor corresponding to the scale used, as 
follows: 

Spring. 8 12 16 20 24 30 32 40 48 

Factor. 02 0'3 04 0'5 06 075 08 DO T4 

The numbers engraved upon the sliding-bar, A, serve for the 
calculation of the contents of surfaces, for which special instruc¬ 
tions are required. The arms of these planimeters are made hol¬ 
low and composed of the best grade of German silver, the whole 
instrument being made with great precision, accuracy, and skill. 
They are manufactured by the Crosby Steam Gauge and Valve 
Company, Boston, Mass. The same firm makes two other styles 
of planimeters, one corresponding with the common instrument in 
use, which has only one wheel, as shown on page 323, and another 
similar to it, having two wheels. 

Crosby’s Improved Steam-Pressure, Hydraulic, Combina¬ 
tion, Vacuum, and Self-Testing Gauges. 

Steam Gauges. —About the year 1849, Eugene Bourdon, of 
France, discovered that the free end or ends of a flattened me¬ 
tallic tube possessed of sufficient elasticity for use as a spring, 
would move when pressure was exerted through the medium of a 

2K 










658 


THE ENGINEER’S HANDY-BOOK. 




fluid applied externally or internally; that the motion was 
in direct proportion to the pressure applied; and that when the 

pressure was removed they 
would assume their former 
position. From this circum¬ 
stance, he conceived the idea 
of a new pressure gauge, in 
which the bent tube should 
be the main spring or means 
of motion. But, though it 
was generally conceded at 
that time that the hollow 
tube spring gauge, as invent¬ 
ed by Bourdon, excelled in 

delicacy and sensitiveness 
Exterior View of Crosby’s Steam any prev ious mechanical ar¬ 
rangement employed for that 
purpose, nevertheless, it was demonstrated by experience that such 
a device, owing to its pecu¬ 
liar construction, was not well 
adapted for all the purposes for 
which pressure gauges are em¬ 
ployed, as, in consequence of 
being held only at one end, it 
would vibrate from a sudden 
shock or slight change of press¬ 
ure, thus causing the pointer to 
oscillate on the dial-plate, in¬ 
ducing friction and wear, and 
rendering the indications of 
the gauge uncertain and delu¬ 
sive. Besides, the dip of such Interior View of the Original 
a spring caused it to retain a Bourdon Steam Gauge. 

portion of the water condensed in it, thus rendering it liable to 
burst in cold weather, to be strained by freezing, and lose its tension. 










































THE ENGINEER^ HANDY-BOOK. 


659 



Interior View of Crosby’s 
Steam Gauge. 


To overcome these defects, numerous devices have been 
suggested and tried, but they 
almost invariably embodied the 
same defects as those above 
mentioned, and were subject to 
the same errors, the gravest of 
which arose from the straight¬ 
ening or setting of the springs. 

Steam users are more indebted 
to George H. Crosby for reme¬ 
dying the foregoing defects in 
pressure gauges, and for the pro¬ 
duction of a perfectly reliable 
steam gauge, than to any one 
previous to his time, as he dis¬ 
covered, by observation and ex¬ 
periment, that only the horizontal motion of the free ends of the 
springs or tubes, while under varying pressure, had been used 
heretofore, and that they had a perpendicular or upward action, 

as well, when the springs were of proper length and shape, and 
* • 

that bv uniting these motions by proper mechanism, it could all 
be transmitted to the pointer. In accomplishing this, he discov¬ 
ered that a firmer and stiffer spring than any heretofore used for 
the same pressure was an absolute necessity. And as a result, 
no pressure over that indicated by the pointer on the dial will 
affect their original elasticity, and vibration of the pointer under 
varying pressures is obviated; besides, in consequence of the spring 
being held at the lowest points, they have no dip, which arrange¬ 
ment admits of the water returning to the siphon, thus preventing 
freezing. Thus it would seem that, while the Crosby gauges em¬ 
brace all the desirable points in the original Bourdon gauge, they 
also embody many others which have been demonstrated by expe¬ 
rience to be absolute necessities in the construction of an accurate, 
reliable, and serviceable steam gauge. 








































660 


THE ENGINEER’S HANDY-BOOK. 




Crosby’s Self-Testing Steam Gauge. 


Self-Testing Steam Gauges. —This class of gauges is of great 
importance, convenience, and utility, as the engineer in charge can 
always ascertain whether his gauge is correct or not by observing 

the following instructions: 
Set off all pressure that may 
be on the gauge, after which 
the pointer will fall to zero ; 
then unscrew the plug on the 
left-hand side, which uncov¬ 
ers the hook. To this hook 
hang the first weight by the 
spindle. This is marked by 
a certain number, and the 
pointer should travel at once 
to the corresponding number 
on the dial, if correct at this 
point. But if the pointer 
stands below or above this 
number, it will indicate just how much the gauge is “out,” and in 
which direction. Proceed by 
adding the next higher num¬ 
bered weight, and continue as 
before. 

Vacuum Gauges. —The con¬ 
ditions under which vacuum 
gauges act are the reverse of 
steam gauges, as, in the vacu¬ 
um gauge, the interior of the 
tube is influenced by the vacu¬ 
um, while its exterior is ex¬ 
posed to the action of the at¬ 
mosphere. These gauges are 
manufactured by the Crosby Crosby ’ s Vacuum Gauge ' 

Steam Gauge and Valve Company, Boston, Mass., and are all 
tested by a mercury column before being put in use. 












the engineer’s handy-book 


661 



Corliss Engine. 














































































Back View of the Atlas Corliss Engine 


662 



































































































































































































































































































































THE ENGINEER’S HANDY-BOOK. 


663 


The Atlas Corliss Engine. 

The cuts on pages 661, 662, show a front and back view of 
the Atlas Corliss engine. As will be observed, the frame is of the 
girder pattern; a form which has been more extensively copied, 
for the past twenty years, by engineers and steam-engine builders 
both in this country and Europe, than any other. Though a Cor¬ 
liss engine in every respect, it differs from others of the same type 
in many very important features; one of which is, that the main 
frame, hind leg, and main-bearing are cast in one solid piece, 
which is not generally the case with other Corliss engines, as, in 
most instances, the main-bearing and its supports are cast sepa¬ 
rately, and bolted to the frame; another is, that the horizontal 
section of the frame is deeper and heavier than in most Corliss 
engines, while a deep rib, running to the base of the legs, insures 
additional rigidity and stiffness. The frame, as in the case of all 
engines of the Corliss type, is faced up at the front end, to receive 
the cylinder, which rests on a pedestal of ample proportions. In 
consequence of the large metal surface brought in contact with 
the foundation, the weight of the engine is more uniformly distrib¬ 
uted, and the jar, which is so detrimental to the stability of many 
types of engines, is entirely obviated. 

While the steam- and exhaust-valves and the cut-off arrange¬ 
ments are essentially the same as in most Corliss engines, the 
mechanism which works the valves and controls the cut-off, is 
entirely different. In the ordinary Corliss engine, only one ec¬ 
centric is employed to operate the steam- and exhaust-valves, 
through the medium of a wrist-plate, which must be so connected 
with the eccentric, as to change the direction of its motion at the 
proper time for opening and closing the steam- and exhaust- 
valves. To accomplish this object, the eccentric must be placed 
nearly at a right angle with the crank; in consequence of which 
its direction changes at about half-stroke; the result of which is, 
that the cut-off' is limited to the preceding portion of the stroke, 
as the clutch must be detached during the forward motion. In 













664 


THE ENGINEER’S HANDY-BOOK. 


the Atlas engine, this difficulty is remedied, as two eccentrics are 
used — one for the steam- and the other for the exhaust-valves, 
each of which is set independently, for the most accurate per¬ 
formance of its own work. The exhaust eccentric has nearly the 
same angular position as the single eccentric in ordinary Corliss 
engines. The cut-off eccentric is placed nearly 90 degrees behind 
it, and therefore does not change the direction of the cut-off clutch, 
until a correspondingly later period in the stroke is reached, which 
is a very important feature in itself. 

The manner in which the eccentrics receive their motion is dif¬ 
ferent from that generally employed, as, instead of being rotated 
on the crank-shaft, they are placed on a supplementary or counter 
shaft, which has the same motion as the main shaft, and is situated 
directly under the cylinder end of the frame. This eccentric 
shaft is operated through the medium of gears from the main 
shaft, through a side shaft, which is located directly under the 
horizontal rib of the frame. The side shaft also operates the gov¬ 
ernor, thus dispensing with the governor-belt and its necessary 
risk and uncertainty. The governor is of the “ Porter ” type, 
which has been successfully applied to engines on which most 
other governors have failed to give satisfactory results. This is 
due to the fact, that the heavy centre weight gives the constant 
force of gravity acting downwards; while the centrifugal force of 
the rapidly revolving balls is the variable force, and acts upwards 
through the joints of the governor; the result of which is, that the 
governor rises or falls, as the variable force is greater or less than 
the constant force. It is very powerful and sensitive, and holds 
the engine in perfect control under the most varying circum¬ 
stances of load and pressure. It is also provided with an auto¬ 
matic stop, which becomes operative in case of accident. 

The valves and cut-off mechanism are essentially the same in 
the Atlas as in most other Corliss engines, as may be seen in 
the cuts on pages 284, 285. 

A is the valve-stem, as shown in Fig. 1. B is a bell-crank fast¬ 
ened to the valve-stem, by which motion is communicated to the 



THE ENGINEER’S HANDY-BOOK. 


665 


valve. C is the cut-off clutch, which is made of gun-metal and 
faced with hardened steel. D is a case-hardened block, having a 
large bearing in the bell-crank, B , which allows it to adapt itself 
freely to any angular position. This block is virtually a part of 
the bell-crank, and contains a hole at right angles to the axis 
of its bearing, through which the small end of the rod, F, which 



carries the cut-off clutch, is passed, and receives its motion from 
the cut-off eccentric by means of a rocking-plate on the side of the 
cylinder. G is the dash-pot rod, to which a weight is attached, 
for the purpose of closing the valves promptly when the cut-off 
is effected. H is the governor-rod ; it varies the angular position 
of the governor-toe, F, as the governor rises and falls, and so 
56 * 




















































































































































































































































666 


THE ENGINEER’S HANDY-BOOK. 


determines the time of cut-off. K is the governor-toe, and is sup¬ 
ported on a bushing concentric with the valve-stem. The cut-off 
occurs when the governor-toe, K, depresses the cut-off clutch, C, suf¬ 
ficiently to detach it at the point, E , from the bell-crank, B, allow¬ 
ing the unsupported weight of the dash-pot to close the valve by 
its fall. 

A cross-section of the cylinder through the steam- and exhaust- 
ports is shown in Fig. 2. 



A is the bell-crank, connected by the cut-off clutch directly to 
the rocking-plate. B is the stuffing-box, which has a very long 
bearing between the ground-joints of the collar and the gland at 
the outside. C is an out-board bearing fitted with a bushing, the 
inside of which forms a bearing, the cut-off toe of the governor 
































































































THE ENGINEER'S HANDY-BOOK. 


667 


being carried on its outer surface. The advantage of this arrange¬ 
ment is, that it prevents the valve-stems from springing, which 
would have a tendency to increase their friction, and cause them 
to wear out of round; while, in consequence of the brackets being 
hollow, they form a receptacle for the drips from the valve-stem, 
stuffing-boxes, and insure perfect drainage. There are many 
points of excellence to be noticed in the design and construction 
of these engines, among which are simplicity of design, convenient 
arrangements for accurate adjustment of the different parts, and 
independent steam- and exhaust-valve motions. The cross-head 
bearings are flat, and so arranged that they may be repaired or 
renewed at short notice and trifling expense. Besides, the cross¬ 
head wrist-pin is placed both in the horizontal and vertical centre 
lines of the bearing surfaces, thus relieving the cross-head of the 
excessive weight and severe strain incident to an overhanging 
connection. 

The Atlas Corliss engines are built of excellent material, 
thoroughly fitted, and tastefully finished. The bearings for the 
rubbing, reciprocating, and revolving surfaces are ample, thus 
preventing the possibility of rapid wear and the necessity of ex¬ 
pensive repairs. The fly-wheels are turned on the face and sides, 
and accurately balanced, which insures smooth running; while the 
cylinders are covered with “asbestos” and cast-iron lagging, which 
prevents condensation and insures economy. The steam-piston 
packing used is Babbit & Harris’s patent (an illustration of which 
may be seen on page 167), which has been generally adopted by 
the builders of the best class of steam-engines in the country, and 
has the reputation of giving entire satisfaction. 

The Atlas engines are built, both condensing and non-condens¬ 
ing, of any power to meet the requirements of purchasers, and for 
whatever purpose employed, whether for milling, manufacturing, 
or pumping, have the reputation of giving entire satisfaction. 
They are manufactured at the Atlas Corliss Engine Works, In¬ 
dianapolis, Indiana. 






668 


THE ENGINEER’S HANDY-BOOK. 

Questions, 

THE ANSWERS TO WHICH WILL BE FOUND IN THE TEXT. 
What is acceleration ? 

Define the term affinity. 

What constitutes an angle? 

Explain the principle embraced in the use of axles. 

Give the meaning of the term attraction. 

What is meant by capillary attractions? 

Define the terms gravity and centre of gravity. 

Give the meaning of the terms adhesion and cohesion. 

Under what two heads may elastic fluids be classified? 

Define the term elasticity. 

Has the term energy any definite meaning when applied to 

mechanics ? 

What is force? 

Define the term focus as used in geometry. 

What is meant bv the term friction ? 

J 

Give the meaning of the terms hydrodynamics, hydrostatics, and 
hydraulics. 

Explain the formation of the hyperbola. 

Define the term impact. 

What is meant by the term impenetrability? 


669 


THE ENGINEER’S HANDY - BOOK. 

Define the term impetus, as applied to mechanics. 

What is meant by the incidence, as applied to mechanics? 

Explain the meaning of the term inclination. 

To what class of the mechanical powers does the inclined plane 
belong ? 

What is the meaning of the term inertia? 

Under what three classes may levers be divided? 

Give the definition of the term machine. 

What physical elements are embraced under the head of me¬ 
chanics ? 

What is meant by the modulus of the elasticity of any sub¬ 
stance ? 

Give the meaning of the term momentum. 

What is meant by motion, as applied to mechanics? 

Enumerate the different kinds of motions. 

Define the centre of oscillation. 

Explain the mechanical principles represented iu the vibration 
of the pendulum. 

Define the centre of percussion. 

Why is perpetual motion an impossibility? 

Explain the meaning of the term pneumatics. 

Of what two forces is power the product? 

What is the difference between pressure and weight? 







670 the engineer's handy-book. 

What kind of machines may be termed prime movers? 

What is the mechanical principle involved in the use of the 
pulley ? 

To which of the mechanical powers is the screw most nearly 
allied? 

Give the meaning of the term resilience. 

Define the science of statics. 

What is meant by strength, when applied to mechanics? 

Enumerate the different kinds of strength. 

Give the meaning of the word tools. 

Define the term torsion. 

What is meant by the term velocity? 

What is understood by the term weight? 

Under which of the mechanical powers may the wheel and 
axle be classed? 

What mechanical principles are embodied in the wedge? 

Give the atomic weights and chemical equivalents of the dif¬ 
ferent metals in use at the present day. 

Which is the most useful metal ? 

Give the weight of a cubic foot of wrought- or cast-iron. 

Give the component parts of cast-iron. 

Of what two elements is steel composed ? 

Give the heat-conducting properties of copper, brass, cast- and 
wrought-iron. 


671 


THE ENGINEER^ HANDY-BOOK, 

Give the tensile strength of copper, brass, gun-metal, wrought- 
and cast-iron. 

Give the proportions of carbon in the various grades of iron 
and steel. 

Give the different proportions of the metals which form the 
basis of brass, Muntz metal, gun-metal, Babbitt metal, and bronze 
alloy. 

\ 

Give the composition of fusible metal which melts at a tem¬ 
perature of 212° Fall. 

Give the rule for finding the approximate weight of iron cast¬ 
ings from the weight of the pattern. 

Give the shrinkage various metals undergo in the process of 
casting. 

Give the weight and bulk of several substances in cubic feet, 
pounds, and tons. 

Give the extension of wrought- and cast-iron at various tem¬ 
peratures. 

Does wrought-iron increase in heat up to a certain tempera¬ 
ture ? 

Is the tensile strength of copper increased by the application 
of heat? 

Give the composition of a good non-conductor for preventing 
radiation of heat in steam-boilers, cylinders, pipes, etc. 

Give the component parts of a good durable cement for steam- 
joints. 

What advantages does belting possess over cog-gearing, and 
vice versCi ? 












672 the engineer’s handy-book. 

From what principle do belts derive their power to transmit 
motion ? 

What are the necessary characteristics of good belting? 

What conditions are necessary to obtain the greatest percentage 
of power from any belt ? 

What advantages have double and single belts, and vice versa ? 

How would you test the quality of belting? 

How would you proceed to make belts run on the centreTof 
pulleys ? 

What are the advantages of rubber belts over leather, and vice 

versa ? 

Give the rule for finding the length of a belt. 

Give the rule for finding the number of horse-power a belt can 
transmit. 

Give the rule for finding the change in length in a belt when 
one of the pulleys is changed. 

Explain the most practicable method of putting on belts. 

State the precautions to prevent accidents when throwing on 
or taking off belts. 

Give the rules for finding the size of pulleys for any required 
speed. 



/ 


INDEX. 


A. B. or Aba, 264. 

Acceleration, 587. 

Accidents by revolving shafts, how to 
prevent, 643. 

Actual extension of wrought-iron at va¬ 
rious temperatures, table showing, 
621. 

Adhesive cement, how to make a 
good,636. 

Adiabatic, 263. 

Adjuncts of steam-boiler, technical terms 
applied to, 476. 

Adjustable cut-off, 227. 

Adjustments, most accurate methods of 
testing, 274. 

Admission, 263. 

Affinity, 587. 

Aggregate strain caused by pressure of 
steam on shells of boilers, rule for 
finding, 451. 

Air, 496. 

Air-casing, 476. 

Air-pump and condenser, independent, 
345. 

Air-pump bucket, 356, 357. 
double-acting, 356. 
pet-cock or valve, 357. 
piston, 356. 
plunger, 356. 
rods, 357. 
ship’s side, 357. 
trunk, 356 

Air-pumps, 353. 
capacity, 354. 
independent, 355. 
vertical, 354. 

Air-valve, 355. 

Alkali, 534. 

Alloy, bronze, 616. 

Alloys and compositions, 616. 
metals, 612. 

Altitude, apparent, 376. 

57 


Altitude, meridian, 376. 
observed, 376. 

of highest mountains in the world, 500. 
true, 376. 

Altitudes above sea-level, table of, 498. 
Ammonia, 5:14. 

Amplitude, 376. 

Analysis, 534. 
chemical, 506. 
of diagrams, 271. 
of sea-water, 457. 

Angle, 587. 
irons, 476. 

Angular advance of eccentric, 183. 
Anthracite coal, composition of, 511. 
Apparent altitude, 376. 
time, 381. 

Application of theoretic curves. 280. 
Appointments as cadet engineers in the 
U. S. Navy, necessary qualifications 
of candidates applying for, 40. 
Approximate weight of iron castings 
from patterns, rule for finding, 619. 
Areas of circles, 536. 

Arithmetic, decimal, 560. 

examination in. 48. 

Ascension, right, 381. 

Assistant engineer, first, 58. 

in the U. S. revenue cutter service, 
standard of examination for, 58. 
Astronomical time, 381. 

Asymptote, 263, 

Atlas Corliss engine, 663. 

Atmosphere, 496. 

Atom, 534. 

Atoms and molecules, 566. 

Attraction, 588. 

capillary, 589. 

Augmentation, 381. 

Automatic cut-off engine, Brown, 88. 
Buckeye, the, 488. 

Douglass, the, 159. 


673 











674 


INDEX 


Automatic cut-off engine, Fitchburg 

Steam-Engine Company’s, 647. 
Putnam Machine Company’s, 138. 
Watertown, the, 194. 

Wheelock, the. 214. 

Woodbury, Booth & Pryor, 52. 
Wright’s, 38. 

Automatic cut-off engines, diagrams 
taken from, 278. 

high-pressure engine, the Greene, 150. 
high-pressure engine, the Woodbury & 
Beach, 124. 

Automatic cut-off and throttling engines, 
130. 

valve-gear, 227. 

Average crushing load of different ma¬ 
terials, table showing, 617. 

Axle, 588. 

and wheel, the, 611. 

Azimuth, 376. 

Babbitt’s metal, 616. 

Back eccentric, 183. 

Balance-engine, Well’s two-piston, 232. 

valves, 228. 

Bank fires, 462. 

Barometer, the, 364. 

Bases, 534. 

Bearings, cross-head, 181. 

Bed-plates and housings, 163. 
Bell-signals, marine, 390. 

Belt, how to put on a, 644. 

Belting, 637. 

Belts, rubber and leather, 642. 

Black finish for brass, 619. 

Blast-pipe, 462. 

Blow-off cocks, 462. 

Boiler materials, 480. 

plates, practical limits to thickness of, 
485. 

stays, 453. 

Boilers, technical terms employed in re¬ 
lation to. 462. 

Boiling-point, 503. 

for fresh water at different altitudes 
above sea-level, table showing, 520. 
of salt water at different degrees of 
density, when barometer stands at 
30 inches, table showing, 362. 

Bolts, cylinder-head, 166. 

stay, 454. 

Bonnet, 160. 

Boss of crank, 185. 

Bourdon spring steam-gauge, 370. 


Brass and glass, cement for, 637. 
black finish for, 619. 
castings, lacquer for, 619. 

Brasses, 160. 

Breaking-strain of iron and copper stay- 
bolts, table showing, 455. 

Bronze alloy, 616. 

Brown automatic cut-off steam-engine, 88. 
Bucket, air-pump, 356, 357. 

Buckeye automatic cut-off engine, 488. 
Bursting-pressure of cylindrical boilers 
with riveted seams, rule for finding, 
448. 

steam-boilers, 448. 

Cadet engineers in the U. S. Navy, 40. 
Calcination, 534. 

Calking, 463. 

Candidates applying for appointments 
as cadet engineers in the U. S. Navy, 
necessary qualifications of, 40. 
examination of, 40. 

for the U. S. revenue service, qualifica¬ 
tions of, 57. 

Capacity of air-pumps, 354. 

of cisterns and tanks, table showing, 
521. 

in gallons for each 10-inch depth, table 

showing, 523. 
unit of, 563. 

Capillary attraction, 589. 

Carbon, 532. 

Cards, indicator. 262. 

Care and management of steam-boilers, 
instructions for, 478. 
of steam-engines, instructions for, 235. 
Causes of knocking in steam-engines, 153. 
Celestial object, hour-angle of a, 378. 
Cement for brass and glass, 637. v 

fastening leather to iron, china, or 
glass, 636. 
leather, 636. 
leather belting, 636. 
rubber belting, 637. 
rust-joints, 635. 

steam-joints and patching steam-boil¬ 
ers, 634. 

stone or marble, 637. 

Central, mechanical, and dynamical 
forces, definition of, 587. 

Centre of gravity, 589. 

gyration, 593. 1 

oscillation, 603. 

Charcoal, 533. 




INDEX 


675 


Check chamber, 476. 
valve, 476. 

Chemical analysis, 506. 

properties of coal, 504. 

Chimneys, draught in, 469. 

Cipher, the, 542. 

Circle, valve, 218. 

Circles, areas of, 536. 

Circular-saws, speed of, 632. 
Circulating-pump, independent ma¬ 
rine, 358. 

Civil time, 381. 

Clearance, 264. 

the term, 122. 

Clipper injector, the, 426. 

table of capacities of, 428. 
Coefficients of friction between plane 
surfaces, table of, 633. 

Cohesion, 589. 

Coil of belting, how to measure, 644. 
Collapsing-pressure of boiler-tiues, rule 
for finding, 452. 

Combination, 534. 

Combustion, 510. 
spontaneous, 512. 

Common and decimal fractions, table of, 
561. 

Comparative efficiency of screw-propel¬ 
ler and paddle-wheel, 399. 
value of different kinds of wood for 
fuel, 505. 

Compass, deviation of the, 377. 
error of the, 377. 
variation of the, 377. 

Composition of anthracite coal, 511. 
Compositions and alloys, 616. 
Compound, 535. 

engines, 109. 

Compressibility, 503. 

Compression, 264. 

Condensation, 503. 

Condenser and air-pump, independent, 
345. 

injector, the, 344. 

Condensers, 338. 
jet, 340. 
surface, 340. 

Condensing and non-condensing, econ¬ 
omy in modern steam-engines, 107. 
Condensing-engines, steam-pumps for, 
403. 

over the non-condensing engine, econ¬ 
omy of the, 107. 

Conductibility, 503. 


Conductors’ signals, 394. 

Conic section, 51. 

Connecting-pipes, 476. 

rod, piston, and crank connections, 
175. 

Contents of an elliptic or oval tank in 
cubic feet or gallons, rule for finding, 
523. 

Cooling of liquids and solids, 510. 

surface in tubes of surface condensers, 
rule for finding, 343. 

Copper, 615. 

Corliss engine, Atlas, 663. 

Centennial, 25. 

Harris, 95. 

Reynolds, 177. 

Wetherill, 583. 

Corrosion, and its analogy to combus¬ 
tion, 460. 
external, 460. 
internal, 460. 

Counter has been working into minutes, 
to reduce the time the, 368. 

Covin terbore, 160. 

Course, 376. 

made good, 376. 
magnetic, 376. 
true, 376. 

Crab-claw, 229. 

Crank, the, 183. 
base of the, 185. 

connections, piston, and connecting- 
rod, 175. 
pins, 185. 

Crank-shaft journals and main-bearings, 
187. 

to determine the diameter of the. 135. 
Cranks of steam-engines to their shafts, 
fitting the, 137. 

Cross-head bearings, 181. 

Crown-bars, 476. 
braces, 477. 
sheet, 476. 

Cubical contents of a triangular tank, 
rule for finding, 524. 

Curvilinear seams, 462. 

Cushion, 264. 

Cut-off and throttling engines, automatic, 
130. 

an adjustable, 227. 
a positive, 227. 

engines, automatic, diagrams taken 
from, 278. 
independent, 227. 








676 


INDEX. 


Cut-off, riding, 227. 

to equalize the, 208. 

Cut-offs, steam-engine, 132. 
Cylimler-boilers, rule for, 453. 
efficiency, 264. 
head-bolts, 166. 

Cylinders, steam, 164. 

Cylindrical steam-boilers, bursting press¬ 
ure of, 448. 

Daily average number of gallons of water 
used per individual in different 
cities, table showing, 524. 

Dashers, 477. 

Dasli-pot, 228. 

Days in different countries, length of, 382. 
Dead-centre, the, 152. 
plate, 477. 
reckoning, 377. 
weight safety-valves, 469. 

Decimal arithmetic, 560. 

Declination, 377. 

Definition of technical terms applied to 
different kinds of boiler-plate. 486. 
Definitions of central, mechanical, and 
dynamical forces, 587. 

Deflector, 477. 

Degrees of longitude, 379. 

Departure, 377. 
taking a, 377. 

Design of steam-engines, 134. 
Deterioration of steam-boilers, 460. 
Deviation of the compass, 377. 
Diagram, theoretical, 270. 

Diagrams, analysis of, 271. 

indicator, 262, 291-320. 

Diagrams taken from automatic cut-off 
engines, 278. 

Diameter of the crank-shaft, to deter¬ 
mine the, 135. 

Diameters and areas of small circles, 
table of, 543. 

Diaphragm-plate, 477. 

Difference, 378. 
of longitude, 380. 

Different parts of steam-engines, techni¬ 
cal terms applied to, 160. 
terms formerly applied to, but which 
have become obsolete, 161. 
Diffusion of vapor, 502. 

Dip of the horizon, 378. 

Directions for operating Sellers’ non-ad- 
justable fixed-nozzle injector, 414. 
for using Eclipse injector, 425. 


Displacement, 264. 

Distance, 377. 
polar, 377. 
zenith, 382. 

Dome, 477. 
stays, 477. 

Double-acting air-pump, 356. 

beat valves, 228. 

Douglas automatic cut-off engine, 159. 
Draught in chimneys, 469. 

I Draw fires, 462. 

Duplicating the parts of steam-engines, 
136. 

Duty, 264. 

Dynamical, central, and mechanical 
forces, definitions of, 587. 

Dynamics, 589. 

Ebullition, 503. 

Eccentric, the, 182. 

angular advance of the, 183. 
back, 183. 
fore, 182. 

throw of the, 183. 

Eclipse injector, 424. 

directions for using, 425. 

Ecliptic, 378. 

Economy in modern steam-engines, con¬ 
densing and non-condensing, 107. 
of high-pressure engines, 131. 
of the condensing over the non-con¬ 
densing engine, 107. 
steam-engine, 325. 
theoretical, 286. 

Effect of size on speed of steam-vessels, 
400. 

Effects of heat upon different bodies, 
table showing, 508. 

Efficiency, cylinder, 264. 

Ejector or lifter, the, 434. 

Elastic fluids, 589. 

Elasticity, 590. 

Emergencies, 584. 

Energy, 590. 

Engine, Atlas Corliss, 286. 

condensing over the non-condensing, 
economy of the, 107. 
high-pressure, waste in the, 103. 
how to reverse an, 145. 
in line, how to put an, 141. 
low-pressure or condensing, waste in, 
104. 

Porter-Alien high-speed, 330. 
surface-condensing, 355. 















INDEX 


677 


Engine, Woodbury, Booth & Pryor auto¬ 
matic cut-off, 52. 

Woodruff & Beach automatic cut-off 
high-pressure, 124. 

Wright’s automatic cut-off, 38. 
Engineer, first assistant, 58. 
Engineering, steam, 27. 

Engineers, facts that should be borne in 
mind by, 34. 

in the U. S. Navy, necessary qualifica¬ 
tions of candidates applying for ap¬ 
pointments as cadets, 40. 
licensing, 30. 
locomotive, 62. 

qualifications of stationary, 60. 
questions for, 99. 

Engines and boilers, valves and cocks 
connected with, 229. 
automatic cut-off and throttling, 130. 
automatic cut-off, diagrams taken 
from, 278. 

Centennial Corliss, 25. 
compound, 109. 

high-pressure, economy of, 131. 

marine, 113. 

simple, 112. 

speed of, 118. 

throttling, 131. 

Equation of time, 382. 

Equator, 378. 

Equivalents, 535. 

Error of the compass, 377. 

Estimating the power of steam-engines, 
118. 

Evaporation, 535. 

Evaporization, 503. 

Examination for assistant engineer in 
the U. S. revenue-cutter service, 58. 
in arithmetic, 43. 
in geography, 47. 
in grammar, 42. 
in natural philosophy, 49. 
of candidates, 40. 

Examinations for the mercantile marine 
service, 59. 

Exhaust- and steam-pipes, 180. 

to equalize the, 210. 

Expansion, 503, 
valve-gear, 227. 

Experiments on iron plates for steam- 
boilers, tabic deduced from, 623. 
Explosions, steam-boiler, 464. 

Faee, valve, 218. 

57 * 


Facts that should be borne in mind by 
engineers. 34. 
steam users. 650. 

Fastening leather to iron, china, or glass. 

cement for, 636. 

Feed-pump pet-cock. 405. 

ram, rule to find diameter of, 404. 
Feed-pump for condensing-engines, 403. 
Feed, to reduce the, 428. 

Feed-water heaters. 474. 

temperature of, 417. 

Fire, 506. 

Fire-engine, the steam, 120. 

Fires, bank, 462. 
draw, 462. 
slice, 462. 
start, 462. 

Firing, manual and mechanical, 461. 

technical terms applied to. 462. 

First assistant engineer. 58. 

Fitchburg steam-engine company s auto¬ 
matic cut-off engine, 647. 

Fitting the cranks of steam-engines to 
their shafts, 137. 

Fittings of marine-boilers, 448. 

Fixed, 535. 

Flame, 506. 

Flexure, 264. 

Flue-boilers, rule for, 453. 

Fluids and vapors, technical terms ap¬ 
plied to, 502. 
elastic, 589. 

Fly-wheels, 192. 

of steam-engines, rule for finding pro¬ 
per weight of, 193. 

Foaming in marine-boilers, 457. 

Focus, 591. 

Force, 590. 

of wind at different velocities, table 
showing, 499. 

Fore eccentric, 182. 

Formula for finding horsepower of 
steam-engines by indicator diagrams, 
318. 319. 

for finding theoretical clearance when 
the scale is known. 316 
for finding the scale of a diagram 
when clearance is known, 317. 
Friction, 59. 

of riveted seams, 463. 
of slide-valves, 221. 
rollers. 591. 

Friedman’s injector, 420. 
table of capacities of, 422. 










678 


INDEX 


Fuel, 503. 

Functions of indicator, 261. 

Funnels, 472. 

Fusible metal, 619. 

Gab-lever, 161. 

Gases, 530. 

Gasket, 477. 

Gauge-cocks, 477. 

Gauges, mercury, 369. 
spring, 369. 
siphon, 369. 
vacuum, 369. 

Gearing, 645. 

Geography, examination in. 47. 
Geometry and trigonometry, 46. 

Gibs, keys, and straps, 188. 

Gill'ard injector, invention of, 407. 
Governors, steam-engine, 197. 
Grammar, examination in, 42. 
Grate-surface, 462. 

Gravity and gravitation, 592. 
centre of, 589. 
specific, 592. 

Green automatic cut-off high-pressure 
engine. 150. 

Gridiron-valves, 228. 

Grummet, 477. 

Gun-metal, 615. 

Gyration, the centre of, 593. 

Hancock inspirator, table of capacities 
of. 432. 

Harris Corliss steam-engine, 95. 

Heat, 507. 
latent, 507. 
of steam, 64. 

latent, 65. 
unit of, 562. 

Heat-conducting properties of different 
metals, table showing, 614. 

Heating in journals and reciprocating 
parts of steam-engines, 202. 

Heating - surface of fire-box boilers — 
locomotive, marine, or stationary — 
rule for finding, 452. 
of vertical tubular-boilers, such as are 
generally used for fire-engines, rule 
for finding, 453. 

Highest mountains, altitude of, in the 
world. 500. 

waterfalls in the world, 500. 
High-pressure engine. Greene, 150. 
valveless engine, Wardwell's, 240. 


High-pressure engine, waste in the, 103. 
Woodruff & Beach automatic cut-off, 
24. 

High-pressure engines, economy of, 131. 
High-speed engine, Porter-Alien, 330. 
Horizon, dip of the, 378. 
visible, 378 

Horse-power for different piston-speeds, 
table of units of, 170. 
indicated, 266. 

to calculate, 285. 
net, 266. 

of steam-engines, formulae for finding, 
by indicator diagrams, 318. 
of waterfalls, rule for finding, 523. 
of wind-storms. 499. 

rule for finding, 500. 
or power of a horse, 593. 

Hotwell thermometer, the, 366. 
Hour-angle of a celestial object, 378. 
Housing, 164. 

Housings and bed-plates, 163. 

How to attach the indicator. 268. 

balance reciprocating and revolving 
parts of vertical engines, 202. 
calculate theoretical rate of water con¬ 
sumption, 288. 

how to determine the amount of lap 
and lead on a valve without opening 
the steam-chest, 218. 
increase the power of steam-engines, 
118, 148. 

keep pipes and pumps from freezing, 

405. 

make a good adhesive cement, 636. 
make belts run on the centre of pul¬ 
leys, 641. 

measure a coil of belting, 644. 
operate the inspirator, 431. 
put an engine in line, 141. 
put on a belt, 644. 
repair steam-engines, 146. 
reverse an engine, 145. 
set up a stationary engine, 143. 
set valves of steam-engines, 224. 
test the quality of leather for belting, 
641. 

use a salinometer, 361. 

H. P., 265. 

H. P.Cyl.,265. 

Hydrodynamics, 593. 

Hydrogen, 532. 

Hyperbola, 265, 594. 

Hyperbolic logarithms, table of, 557. 







INDEX 


679 


Impact, 594. 

Impenetrability, 594. 

Impetus, 595. 

Incidence, 595. 

Inclination, 595. 

Inclined plane, 595. 

Independent air-pumps, 355. 
condenser and air-pump, 345. 
cut-off, 227. 

marine circulating-pump, 358. 
Indicated horse-power, 266. 

to calculate, 285. 

Indicator cards, 262. 

Crosby, 258. 
diagrams, 262, 291-320. 

show what, and how, 321. 
functions of, 261. 
how to attach the, 268. 
steam-engine: its invention and im¬ 
provement, 258. 
technical terms used, 263. 

Inertia, 596. 

Initial pressure, 266. 
or steam-line, 282. 

Injection-water required to condense a 
certain volume of steam, relative 
quantity of, 342. 

Injector, clipper, 426. 

table of capacities of, 428. 
condenser, 344. 

Eclipse, 424. 

Friedman’s, 420. 

Keystone, 422. 
lifting, 423. 

method of starting the, 434. 

Rue’s “ Little Giant,” 418. 
to start the, 423. 

with lifting attachment for stationary 
boilers, Sellers’ non-adjusting fixed- 
nozzle, 412. 

Wm. Sellers & Co.’s, 408. 

Injectors, 406. 

Instructions for setting up, properly at¬ 
taching, and adjusting, 432. 
Inspirator, 430. 0 

Hancock, table of capacities of, 432. 
how to operate the, 431. 
instructions for setting up, properly at¬ 
taching, and adjusting injectors, 432. 
the care and management of steam- 
boilers, 478. 

the care of steam-engines, 235. 
Intercepter or separator, 473. 

Internal strain to which boilers are sub¬ 


jected when under pressure, rule for 
finding, 451. 

Invention of Giffard injector, 407. 
Isothermal, 265. 

Jacket, steam, 66. 

Jamison’s steam water-ejector, 435. 

table of capacities of, 435. 

Jam-nuts, 160. 

Jet condensers, 340. 

Journals and reciprocating parts of 
steam-engines, heating in, 202. 

Keys, gibs, and straps, 188. 

Keystone injector, 422. 

lifting injector, 423. 

Knees, 478. 

Lacquer for brass castings, 619. 

Lamps, signals by, 391. 

Lane spring steam-gauge, 369. 

Lap and lead on a valve without opening 
the steam-chest, how to determine 
the amount of, 218. 
on the valve, 217. 

Latent heat, 507. 
of steam, 65. 

of various substances, table showing 
the, 508. 

Latitude, 378. 

and longitude of places, table of, 384. 
Lead, loss of, 217. 

on the steam end, 217. 
on the valve, 317. 

Leather belting, cement for, 636. 
Leeway, 379. 

Length of days in different countries, 

382. 

of stroke and number of revolutions for 
different piston-speeds in feet per 
minute, table showing, 172. 
unit of, 562. 

Letter b, 264. 

Letter T, 268*. 

Levers, 596. 
spring, 229, 

Lexicon of definitions of central, me¬ 
chanical, and dynamical forces, 587. 
Licensing engineers, 30. 

Lifter or ejector, the, 434. 

Lifters, 229. 

Lift of safety-valves, 467. 

Lifting and stationary links, 192. 
injector, the Keystone, 423, 












680 


INDEX 


Light signals for ocean steamships, 390. 
Line and line, 204. 

Linear dilatation of solids by heat, table 
showing, 622. 

expansion of wrought-iron, 621. 

Link, the. 189. 

radius of the, 191. 

Link-motion, the, 189. 

Walschaert, 191. 

Links, lifting and stationary, 192. 

Liquids and solids, cooling of, 510. 

“ Little Giant” injector. Rue’s, 418. 
Location of steam-engines, 329. 

Lock safety-valves, 469. 

Locomotive, 119. 
engineers, 62. 
power of the, 119. 

Logarithms of numbers from 0 to 1000, 
table of, 555. 

Longitude, 379. 
degrees of, 379. 
difference of, 380. 
into time, to reduce, 379. 
Longitudinal seams, 462. 

Loss of lead, 217. 

Low - pressure or condensing engine, 
waste in the, 104. 

L. P. cyl., 265. 

Lubricants, 243. 

Machines, 597. 

Magnetic course. 376. 

Magnitudes and velocities of planets, 
table showing, 375. 

Main-bearings and crank-shaft journals, 
187. 

Manual and mechanical firing, 461. 
Marine bell-signals, 390. 
boilers, fittings of, 448. 
foaming in, 457 

circulating-pump, independent, 358. 
engine, 113. 
signals, 386. 

steam-engine register, 367. 
whistle-signals, 389. 
wrecking-pump, 359. 

Marine engines, reversing-gear for, 203. 
uncertainty of tests made for the pur¬ 
pose of comparing the relative econ¬ 
omy of, 116. 

Mariner’s compass, the, 373, 

Martin’s upright tubular boiler, 446. 
Materials, boiler, 480. 

Mean effective pressure, 266, 283. 


Mean speed of a steam-vessel, to find, 400. 

time. 381. 

Measurement of screw-propeller, 395. 

Measures and weights. 610. 

Mechanical and manual firing, 461. 

dynamical, and central forces, defini¬ 
tions of, 587. 

Mechanics, 598. 

Mercantile marine service,examinations 
for the, 59. 

Mercury-gauge, 369. 

Meridian, 380. 
altitude, 376. 

Metal, Babbitt's, 616. 
fusible. 619. 

Metals and alloys, 612. 

Method of starting the injector, 434. 

Mile as measured by various nations, table 
of, 382. 

Miles and knots, knots and miles, table 

of, 386. 

Millstones, speed, power, capacity, and 
dress of, 632. 

Mineral substances and their chemical 
equivalents, table of, 612. 

Modulus, 600. 

Molecules and atoms, 566. 

Momentum, 600. 

Most accurate methods of testing the ad¬ 
justments, 274. 

Motion, 601. 

of the paper drum, 262. 
perpetual, 604. 

Movers, prime. 606. 

Multiplication, peculiarities of, 560. 

Muntz metal, 615. 

Natural philosophy, examination in, 49. 

Navigation, technical terms and defini¬ 
tions used in, 376. 

Necessary quantity of water per min¬ 
ute for any engine, rule for finding, 
404. 

Net horse power, 266. 

Neutral, 535. 

Neutralization, 535. 

Nitrogen, 531. 

Non-condensing engine, economy of the 

condensing over the, 107. 

Non-conducting covering for steam- 
boilers and pipes, 634. 
properties of different materials at even 
thickness, table showing, 510. 

Number of square feet of heating-surface 












I ND EX 


681 


in a tube, or any number of tubes, 
rule for finding, 452. 

Observed altitude, 376. 

Ordinates, 265. 

to space the, 285. 

Oscillation, centre of, 603. 

Over-stroke, 119. 

Oxidation, 535. 

Oxide, 535. 

Oxygen, 531. 

Paddle-wheel, 396. 

Paper drum, motion of, 269. 

Parallax, 380. 

Parallelism, 265. 

Parallels, 378. 

Parts of steam-engines, duplicating the, 
136. 

Peculiarities of multiplication, 560. 

Pendulum, 603. 

Percentage of loss induced by blowing 
off to prevent saturation, rule for 
finding, 364. 

Percussion, 603. 

Perpetual motion, 604. 

Pet-cock feed-pump, 405. 

Phosphate, 535. 

Pins, crank, 185. 

Pipe diagram, 266. 

swivel, 161. 

Pipes, 231. 

and pumps from freezing, how to keep, 
405. 

Piston air-pump, 356. 

, connecting-rod, and crank connec¬ 
tions, 175. 

rod and valve-rod packing, and how 
to use it, 237. 
rods, 169. 

Pistons, steam, 167. 

Pitman, 161. 

Plane, the inclined, 595. 

Planimeter, the, 323 656. 

Plate, wrist, 229. 

Plug-tree, 161. 

Plunger air-pump, 356. 

Pneumatics, 605. 

Points of the compass, table of rhumbs, 
or, 374. 

Polar distance, 377. 

Poles, 380. 

Porter-Allen high-speed engine, 330. 
Port side, 380. 


Positive cut-off, 227. 

Power, 606. 

and speed of stearn-vessels, relation 
between, 399. 
of a horse, 593. 
of the locomotive, 119. 
of steam-engines, 117. 
estimating the, 118. 
how to increase the, 118. 
required to raise water to different al¬ 
titudes varying from 1 foot to 20,000 
feet, table showing, 522. 

Practical limits to thickness of boiler¬ 
plates, 485. 

Pressure, 606. 

and temperature of vapors of water 
from 32° to 400° Fah., table showing. 
526. 

mean effective, 266, 283. 

of a diagram from its area, 324. 
on slide-valves, rule for finding the, 222. 
per sq. in. of sectional area in crown- 
sheets of steam-boilers, rule for find¬ 
ing, 451. 

safe-working, 462. 
terminal, 266. 
unit of, 564. 

Prime movers, 606. 

Priming, 458. 

Proper number of revolutions per minute 
of any sized saw, rule for finding, 632. 

Proportion of carbon in various grades 
of iron and steel, table showing, 615. 

Proportions of the United States or Sel¬ 
lers’ standard threads for screws, 
nuts, and bolts, table giving the, 631. 

Pulley, the, 607. 

Pulleys for governors, rules for calculat¬ 
ing the size of, 201. 

Pump-plunger for any engine, rule for 
finding diameter of, 403. 

Pumps, 401. 
air, 353. 

Putnam machine company’s automatic 
cut-oft' engine, 138. 

Pyrites, 536. 

Qualifications of candidates for the U. 
S. revenue service, 57. 
stationary engineers, 60. 

Quantity and weight of water in pipes 1 
fathom in length (6 feet), and of dif¬ 
ferent diameters from 1 to 12 inches, 
518. 









682 


I N V F. X 


Quantity of water per lineal foot in 
pumps, or vertical pipes of different 
diameters. 519. 

of water which any square or rectan¬ 
gular box or tank is capable of con¬ 
taining in cubic feet or U. S. gallons, 
rule for finding, 524. 

Questions for engineers, 99, 162, 246, 334, 
436, 491, 585, 668. 

Radiating properties of different sub¬ 
stances. table showing, 508. 

Radius-bar, 161. 

Radius of the link, 191. 

Railroad signals, 391. 

Reciprocating and revolving parts of 
vertical engines, how to balance, 202. 

Reckoning, dead, 377. 

Refraction, 380. 

Register, marine steam-engine, 367. 

Relation between power and speed of 
steam-vessels, 399. 

Relative economy of marine engines, 
uncertainty of tests made for the 
purpose of comparing the, 116. 
quantity of injection-water required to 
condense a certain volume of steam, 
342. 

volumes of air at various temperatures, 
table showing the, 501. 
weight and volume of different gases, 
table showing, 508. 

Release, 265. 

Releasing valve-gear, 226. 

Relief-valves, 228. 

Remedies for knocking in steam-engines, 
155. 

Resilience, 608. 

Results of experiments made on different 
brands of boiler-iron at the Stevens 
Institute of Technology, 620. 

Rev. or Revs., 266. 

Reversing-gear for marine engines, 203. 
valve-gear, 227. 

Revolutions engine has made during 
voyage, rule for finding number of, 
368. 

Revolving shafts, how to prevent acci¬ 
dents by, 643. 

Reynolds Corliss engine, 177. 

Riding cut-off, 227. 

Right ascension, 381. 

Riveted seams, friction gf, 463. 

Rock-shafts, 181. 


Rods, air-pump, 357. 
piston, 169. 
valve, 182. 

Rollers, friction, 591. 

Rolling circle of a wheel, 398. 

Rotary-valves, 228. 

Rubber and leather belts, 642. 
belting, cement for, 637. 

Rue’s “ Little Giant” injector, 418. 
table of capacities of, 420. 

Rule for cylinder-boilers, 453. 

Rule for finding aggregate strain caused j 
by pressure of steam on shells of 
boilers, 451. 

amount of gain derived from working 
steam expansively, 67. 
approximate weight of iron castings 
from patterns, 619. 

bursting pressure of cylindrical boilers 
with riveted seams, 448. 
centre of gravity of taper-levers, for 
safety-valves, 469. 

change required in length of belt when 
one of the pulleys on which it runs 
is changed for one of different size, 

644. 

collapsing pressure of boiler-flues, 452. 
contents of an elliptic or oval tank in 
cubic feet or gallons, 523. 
cooling surface in tubes of surface con¬ 
densers, 343. 

cubic contents of a steam-cylinder, 166. 
cubical contents of a triangular tank, 
524. 

diameter of a driven pulley for a given 
number of revolutions, 645. 
diameter of a pinion when the diame¬ 
ter of the driver and the number of 
teeth in driver and pinion are given, 

645. 

diameter of pump-plunger for any en¬ 
gine, 403. 

diameter of toothed wheels. 645. 
distance piston is ahead of a central 
position in the cylinder, 176. 
heating surface of fire-box boilers, etc., 
452. 

heating surface of vertical tubular 
boilers, 453. 

horse-power of a locomotive, 120. 
horse-power of a steam-engine by in¬ 
dicator diagrams. 121. 
horse-power of simple condensing en¬ 
gines, 121. 







INDEX 


683 


Rule for finding horse-power of steam- 
engines and fire-engines, 120. 
horse-power of waterfalls, 523. 
horse-power of wind storms, 500. 
internal strain to which boilers are 
subjected when under pressure, 451. 
mean or average pressure in cylinder 
of a steam-engine, 68. 
necessary quantity of water per minute 
for any engine, 404. 

lumber of revolutions engine has 
made during voyage, 368. 
number of revolutions in each wheel 
for a train of spur-wheels, 646. 
number of revolutions of a driver, 646. 
number of revolutions of the last wheel 
in a train of wheels and pinions, 
spurs or bevels, 646. 
number of square feet of heating sur¬ 
face in a tube or any number of 
tubes, 452. 

percentage of loss induced by blowing 
off to prevent saturation, 364. 
point of cut-off’ required to produce a 
given terminal from a given initial 
pressure, 221. 

point of cut-off when the initial and 
mean pressure are known, 221. 
pressure at which a safety-valve is 
weighted when length of lever, 
weight of ball, etc., are known, 468. 
pressure per square inch of sectional 
area or crown-sheets of steam-boil¬ 
ers, 451. 

pressure per square inch when area of 
valve, weight of ball, etc., are known, 
468. 

proper number of revolutions per min¬ 
ute of any sized saw, 632. 
proper thickness for steam-cylinders, 
165. 

proper weight of fly-wheels of steam- 
engines, 193. 

quantity of steam any engine will use 
at each stroke of the piston, 166. 
quantity of water which any square or 
rectangular box or tank is capable 
of containing in cubic feet or U. S. 
gallons, 524. 

required area for chimneys of station¬ 
ary boilers, 473. 

required diameter of cylinder for an 
engine of any given horse-power, 
165. 


Rule for finding required number of teeth 
in a pinion to have any given veloc¬ 
ity, 645. 

required size of a driving-pulley for 
any required speed, 644 
safe external pressure on boiler-flues, 
452. 

safe working-pressure of iron boilers, 
451. 

strain due to pressure of steam on boil¬ 
er-stays, 452. 

strain exerted in a longitudinal direc¬ 
tion by pressure of steam in a boiler, 
449. 

strain exerted in a transverse direction 
by pressure of steam in a boiler, 449. 
strength of single- or double-riveted 
seams, 452. 

weight necessary to put on a safety- 
valve lever, 468. 

width of belt to transmit a given horse¬ 
power, 643. 

Rule for flue-boilers, 453. 
tubular-boilers, 453. 

Rule to find area of a circle, 538. 
a cycloid, 539. 
an ellipse, 539. 
an elliptic segment, 539. 
an hyperbola, 540. 
an oval, 538. 
any polygon, 539. 
parallelogram, 538. 

quadrilateral inscribed in a circle, 539. 

regular polygon, 539. 

sector of a circle, 539. 

segment of a circle, 539. 

trapezoid, 539. 

triangle, 538. 

circumference of a circle, 538. 
circumference of an ellipse or oval, 
538. 

curve surface of any segment or zone 
of a sphere, 541. 

cubic contents of a frustum of a para¬ 
bolic conoid, 541. 

cubic contents of a frustum of a pyra¬ 
mid or a cone, 540. 

cubic contents of a frustum or zone of 
a sphere, 541. 

cubic contents of a parabolic conoid, 
541. 

cubic contents of a prism or a cylinder, 
540. 

cubic contents of a prismoid, 541. 







684 


INDEX 


Rule to find cubic contents of a pyramid 
or a cone, 540. 

cubic contents of a segment of a sphere, 
540. 

cubic contents of a segment of a sphe¬ 
roid, 541. 

cubic contents of a sphere, 541. 

“ “ “ wedge, 541. 

diameter of a circle, 538. 
diameter of feed-pump ram. 404. 
length of an arc of a hyperbola begin¬ 
ning at vertex, 540. 

length of an arc of a parabola cut off 
by a double ordinate to the axis, 539. 
surface of a frustum of a pyramid or 
a cone, 540. 

surface of a prism or a cylinder, 540. 
surface of a pyramid or cone, 540. 
surface of a sphere, 541. 

Rules for calculating number of horse¬ 
powers a belt w 7 ill transmit, 643. 
size of pulleys for governors, 201. 
comparing degrees of temperature in¬ 
dicated by different thermometers, 
366. 

for finding length of belt, 643. 

for finding pressure on slide-valves, 222. 

Rust, 613. 

Rust-joints, cement for, 635. 

Safe external pressure on boiler-flues, rule 
for finding, 452. 

working-pressure of iron boilers, rule 
for finding, 451. 

“'working-pressure, or safe load, 462. 

Safety-valves, 465, 654. 
dead-weight, 469. 
lift of, 467. 
lock, 469. 
spring, 469. 

Sailing distances from New York to dif¬ 
ferent parts of the world, 383. 

Saline, 536. 

Salinometer, 360. 650. 
how to use a, 361. 

Salt in water of different seas, table show¬ 
ing proportion of, 362. 

Saturation, 363, 536. 

Scale, 267. 

in steam-boilers, 455. 

of a diagram, formula for finding, 317. 

Scoggin, 161. 

Screw, 607. 


Screw-propeller, 394. 

and paddle-wheel, comparative effi¬ 
ciency of, 399. 
measurement of, 395. 

Scum-cocks, 478. 

Seams, curvilinear, 462. 
longitudinal, 462. 

Seat-valve, 218. 

Sea-water, analysis of, 457. 

Section, conic, 51. 

Sellers’ injectors, table of capacities of, 417. 
non-adjustable fixed-nozzle injector, 
directions for operating, 414. 
non-adjusting fixed-nozzle injector, 412. 

Semi-diameter, 381. 
rotary valves, 228. 

Sliackle-bar, 161. 

Shafts, rock, 181. 

Ship’s side air-pump, 357. 

Shrinkage of castings of different metals, 
table showing, 620. 

Sidereal time, 381. 

Signals by lamp, 394. 
conductors’, 394. 
enginemen’s, 393. 
for ocean steamships, light, 390. 
marine, 386. 
railroad, 391. 
train, 392. 

Signification of signs used in calcula¬ 
tions, 542. 

Signs used in calculations, signification 
of, 542. 

Simple engines, 112. 

Slice fires, 462. 

Slide-valve, 205. 

Slide-valves, friction of, 221. 

rule for finding pressure on, 222. 

Slip of the screw', 395. 

Smoke, 473, 506. 

Snifting-valve, 341. 

Solder, 617, 619. J 

Space, water, 462. 

Spanner-guard, 478. 

Specific gravity, 592. 

heat of different substances, table 
showing, 509. 

Spectacles, 478. 

Speed of circular-saws, 632. 
of engines, 118. 

of steam-vessels, effect of size on, 400. 
pow'er, capacity, and dress of mill¬ 
stones, 632. 

. 







0 


INDEX 


685 


Spelling, 43. 

Spider, 161. 

Spontaneous combustion, 512. 

Spring, 267. 
gauge, 369. 
levers, 229. 
safety-valves, 469. 
steam-gauge, Bourdon. 370. 

Lane. 369. 

Squares, cubes, and square and cube roots 
of all numbers from 1 to 620, 567. 
Standard of examination for assistant 
engineer in U. S. revenue cutter ser¬ 
vice, 58. 

weights of cast-iron gas- and water- 
pipes, tables showing, 628. 
Starboard side, 381. 

Start fires. 462. 

Starting-valve gear, 228. 

Statics, 608. 

Stationary and lifting links, 192. 
engine, how to set up a, 1-13. 
engineers, qualifications of, 60. 
Stay-bolts, 454. 

tubes, 477. 

Stays, boiler, 453. 

Steam, 63. 
heat of, 64. 
jacket, 66. 
latent heat of, 65. 
ports, 70. 
saturated, 63. 
surcharged, 63. 
temperature of, 63. 
volume of, 64. 

Steam- and exhaust-pipes, ISO. 
Steam-boiler explosions, 464. 
Steam-boilers, 442. 

and pipes, non-conducting covering 
for, 634. 

bursting pressure of cylindrical, 448. 
cylinders, 164. 
deterioration of, 460. 
scale in, 455. 

Steam end, loss on the, 217. 
Steam-engine, Brown automatic cut-off, 
88 . 

cut-offs, 132. 
economy, 325. 
governors, 197. 

Harris Corliss, 95. 

how to increase power of, 148. 

indicator, 251. 

58 


Steam engineering, 27. 

Steam-engines, causes of knocking in, 

153. 

condensing and non-condensing, econ¬ 
omy in modern. 107. 
design of. 134. 
duplicating parts of. .136. 
estimating power of, 118. 
fitting the cranks of, 137. 
heating in journals and reciprocating 
parts of, 202. 

how to increase power of, 118. 
how to repair, 146. 
how to set valves of, 224. 
in general, 102. 
instructions for care of, 235. 
location of, 329. 
power of, 117. 

remedies for knocking in, 155. 

Steam fire-engine, 120. 

Steam-joints and patchingsteam-Doilers, 
cement for. 634. 
line, or initial pressure, 282. 
pistons, 167. 

pressure required to lift and deliver 
water with Sellers’ fixed-nozzle lift¬ 
ing-injector, table showing. 412. 
room, 462. 

water-ejector, Jamison’s, 435. 
table of capacities of, 435. 

Steel, 613. 

Stern-tube, 396. 

Stone or marble, cement for, 637. 

Strain due to pressure of steam on boiler- 
stays, rule for finding, 452. 
exerted in a longitudinal direction by 
pressure of steam in a boiler, 449. 
exerted in a transverse direction by 
pressure of steam in a boiler.. 449. 
that will pull different metals asunder 
on a straight pull, table showing, 618. 
Straps, keys, and gibs, 188. 

Strength, 609. 

of copper boiler-plates at different tem¬ 
peratures, table showing, 623. 
of single- or double-riveted seams, rule 
for finding, 452. 

String, 267. 

Stroke, valve, 218. 

Sulphur, 615. 

Superheaters, 473. 

Surface condensers, 340. 
condensing engine. 355. 












686 


INDEX 




Surface, grate, 462, 
unit of, 563. 

Syplion-gauge, 369. 

Table containing diameters, circumfer¬ 
ences. and areas of circles, etc., 544. 
deduced from experiments on iron 
plates for steam-boilers, 623. 
giving proportions of U. S. or Sellers’ 
standard threads for screws, nuts, 
and bolts, 631. 

of altitudes above sea-level, 498. 
of average performances of different 
designs of pumping-engines, 114,115. 
of capacities of Clipper injectors, 428. 
of capacities of Friedman’s injectors, 
422. 

of capacities of Hancock inspirator, 432. 
of capacities of Jamison’s steam water- 
ejector, 435. 

of capacities of Rue’s “Little Giant” ! 
injector, 420. 

of capacities of Sellers’ injector, 417. 
of coefficients of frictions between 
plane surfaces, 633. 

of common and decimal fractions. 561. 
of constant numbers by which to as¬ 
certain the average of the steam 
against the piston, etc , 69. 
of constant numbers for finding the re¬ 
quired “ lap ” for slide-valves, etc., 70. 
of diameters and areas of small circles, 
543. 

of elastic force, temperature, and vol¬ 
ume of steam, etc., 76-80. 
of hyperbolic logarithms, 68, 557. 
of latitude and longitude of places, 384. 
of logarithms of numbers, etc., 555. 
of mile as measured by various na¬ 
tions, 382. 

of miles and knots, knots and miles, 
386. 

of mineral substances and their chem¬ 
ical equivalents, 612. 
of multipliers, etc., 69. 
of rhumbs, or points of the compass, 
374. 

of sailing distances, etc., in geograph¬ 
ical miles. 383. 

of squares, cubes, and square and cube 
roots of numbers from 1 to 620, 567. 
of units of horse-power for different 
piston-speeds, 170. 


Table of vulgar and decimal fractions of 
an inch, 561. 

showing actual extension of wrought- j 
iron at various temperatures, 621 
showing all the units of length recog- j 
nized in England since the 16th cen 
tury, 565. 

showing amount of “lap” required 
for slide-valves, etc., 220. 
showing average crushing load of dif¬ 
ferent materials, 617. 
showing boiling-point for fresh water 
at different altitudes above sea-level, 

520. 

showing boiling-point of salt water 
at different degrees of density, etc., 

362. 

showing breaking strain of iron and | 
copper stay-bolts, 455. 
showing capacity of cisterns and tanks, 

521. 

showing capacity of cisterns in gallons 
for each 10 inch depth, 523. 
showing daily average number of gal¬ 
lons of water per individual in dif¬ 
ferent cities, etc., 524. 
showing effect of heat upon different 
bodies, 508. 

showing different velocity of steam at 
different pressures, etc., 67. 
showing force of wind, etc., at different 
velocities, 499. 

showing force of uncondensed steam, 
etc., according to temperature, 341. 
showing heat-conducting properties of 
different metals, 614. 
showing increase of sensible and de¬ 
crease of latent heat in steam, 65. 
showing latent heat of various sub¬ 
stances, 508. 

showing length of stroke and number 
of revolutions for different piston- 
speeds in feet per minute, 172. 
showing linear dilatation of solids by 
heat, 622. 

showing magnitudes and velocities of 
planets, 375 

showing maximum and minimum de- j 
livery of Sellers’ self-adjusting in- I 
jector, etc., 416. 

showing non conducting properties of 
different materials at even thickness, 
510. 










INDEX 


687 


Table showing power required to raise 
water to different altitudes, etc., 522. 
showing pressure and temperature of 
vapor of water from 32 c to 400° Fah.. 
526. 

showing proper thickness for steam- 
cylinders from 6 to 90 inches. 166. 
showing proportion of carbon in the 
various grades of iron and steel. 615. 
showing proportion of salt in water of 
different seas, 362. 

showing quantity and weight of water 
in pipes of one fathom in length (6 
feet), etc., 518. 

showing quantity of water per lineal 
foot in pumps, or vertical pipe of 
different diameter, 519. 
showing radiating properties of differ¬ 
ent substances, 508. 

showing relative volumes of air at va¬ 
rious temperatures, 501. 
showing relative weight and volume 
of different gases, 509. 
showing results of experiments made 
on different brands of boiler-iron, 
630. 

showing shrinkage of castings of dif¬ 
ferent metals, 620. 

showing specific heat of different sub¬ 
stances, 509. 

showing standard weights of cast-iron 
water- and gas-pipes, 628. 
showing steam-pressure in pounds per 
gauge, etc., 85. 

showing steam-pressure required to 
lift and deliver water with Sellers’ 
fixed-nozzle lifting injector, 412. 
showing strain that will pull different 
metals asunder on a straight pull, 
618. 

showing strength of copper boiler 
plates at different temperatures, etc., 
623. 

showing temperature and weight of 
steam at different pressures, etc., 
81-84. 

showing temperature of steam at dif¬ 
ferent pressures, etc., 74. 75. 
showing tenacity or tensile strength of 
different metals, 614. 
showing tensile strength of different 
kinds of wood. 618. 

showing temperature of saturated va¬ 


por in atmosphere, according to 
Zeuner. 525. 

Table showing tensile strength of various 
qualities of American and English 
cast-iron, 628. 

showing tensile strength of various 
qualities of American wrought-iron, 
629. 

showing time at different places, 385. 
showing total heat of combustion of 
various fuels, 512. 

showing units of heat required to con¬ 
vert 1 pound of water, at tempera¬ 
ture of 32°, into steam at different 
pressures, 475. 

showing vacuum in inches of mercury 
and pounds pressure per sq. in.. 349. 
showing weight and bulk of different 
substances in cubic feet, pounds, and 
tons, 620. 

showing weight of atmosphere per 
sq in. corresponding with different 
heights of barometer. 365. 
showing weight of boiler-plates 1 foot 
square and from one-sixteenth of an 
inch to an inch thick. 626. 
showing weight of castings by weight 
of the patterns, 620. 

showing weight of cast-iron balls from 
3 to 13 inches in diameter, 624. 
showing weight of cast-iron pipes, etc., 
627. 

showing weight of cast-iron plates per 
superficial foot as per thickness. 624. 
showing weight of different metals per 
cubic foot. 621. 

showing weight of round iron, etc.. 625. 
showing weight of square bar-iron, etc., 
620. 

showing weight of water at different 
temperatures, 520. 

Tables showing average pressure of the 
steam upon the piston throughout 
the stroke, etc., 71-73. 

Taking a departure. 377. 

Technical and chemical terms that bear 
relation to the steam-engine, 534. 
terms and definitions used in naviga¬ 
tion, 376. 

terms applied to adjuncts of steam- 
boiler. 476. 

terms applied to different kinds of 
boiler-plate, 486. 













688 


INDEX. 


Technical terms applied to different 
parts of steam-engines, 160. 
terms applied to firing, 462. 
terms applied to fluids and vapors, 502. 
terms employed in relation to boilers, 
462. 

terms used in connection with employ¬ 
ment of indicator, 263. 

Temperature of feed-water, 417. 

saturated vapor in atmosphere, table 
showing, 525. 
of steam, 63. 

Tenacity or tensile strength of different 
metals, table showing, 614. 

Tensile strength of different kinds of 
wood, table showing, 618. 
strength of various qualities of Amer¬ 
ican cast-iron, 628. 

strength of various qualities of Ameri¬ 
can wrought-iron, 629. 

Terminal pressure, 266. 

Terms formerly applied to different parts 
of steam-engines, but which have 
become obsolete, 161. 

Theoretical clearance when the scale is 
known, formula for finding, 316. 
diagram, 279. 
economy, 286. 

rate of water consumption, how to cal¬ 
culate, 288. 

Theoretic curve, application of, 280. 

Thermal unit, the, 507. 

Thermometer, the Hotwell, 366. 
the Uptake, 366. 

Thermometers, 365. 

rules for comparing degrees of temper¬ 
ature indicated by different, 366. 

Throttle-valves, 228. 

Throttling and automatic cut-off engines, 
130. 

engines, 131. 

Throw of the eccentric, 183. 

Thrust-block, 395. 

Tighteners, 642. 

Time, apparent, 381. 
astronomical, 381. 

at different places at noon, New York, 
table showing, 385. 
civil. 381. 
equation of, 382. 
mean, 381. 

or duration, unit of, 561. 
sidereal, 381. 


To calculate the indicated horse-power, 
285. 

To compromise between unequal lead and 
cut-off, 210. 

To equalize the cut-off, 208. 
the exhaust, 210. 

To find diameter of engine shaft-pulley, 201. 
diameter of governor shaft-pulley, 201. 
mean effective pressure of a diagram 
from its area, 324. 
mean speed of a steam-vessel, 400. 

Tools, 609. 

To reduce longitude into time, 379. 
the feed, 428. 

the time the counter has been working 
into minutes, 368. 

Torsion, 609. 

To space the ordinates, 285. 
start the injector, 423. 

Total heat of combustion of various fuels, 
table showing, 512. 

Train signal, 392. 

Trigonometry and geometry, 46. 

Trips, 229. 

Trophies, 381. 

True altitude, 376. 
course, 376. 

Trunk, 161. 

air-pump, 356. 

Trunnions, 161. 

Tube-sheets, 478. 

Tubular-boilers, rule for, 45. 

Uncertainty of tests made for the pur¬ 
pose of comparing the relative econ¬ 
omy of marine engines, 116. 

Uncondensetl steam arising from water 
in condenser resists ascent or descent 
of piston, table showing force with 
which, 341. 

Undulating, 268. 

Unequal lead and cut-off, to compromise 

between, 210. 

Unit of capacity, 563. 
of heat, 562. 
of length, 562. 
of pressure, 564. 
of surface, 563. 
of time or duration, 564. 
of velocity, 564. 
of weight, 563. 
of work, 564. 
the thermal, 507. 











INDEX 


689 


Units, 562. 

of heat required to convert 1 pound 
of water, at temperature of 32°, into 
steam at different pressures, 475. 
of length recognized in England since 
the sixteenth century, table showing, 
565. 

Upright tubular-boiler, Martin’s, 446. 
Uptake thermometer, the, 366. 

U. S. revenue service, qualifications of 
candidates for the, 57. 

Vacuum, 348. 
gauges, 369. 

in inches of mercury and pounds 
pressure per square inch, table show¬ 
ing, 349. 

Value, comparative, of different kinds of 
wood for fuel, 505. 

of wood as fuel compared with coal,504. 
Valve circle, 218. 
face, 218. 
lap on the, 217. 
lead on the, 217. 
rods, 182. 
seat, 218. 
snifting, 341. 
stroke, 218. 

Valve-gear and valves, 226. 
automatic cut-off, 217. 
expansion, 227. 
releasing, 226. 
reversing, 227. 
whole-stroke, 227. 

Valve.rod and piston-rod packing, and 
how to use it, 237. 

Valves and cocks connected with engines 
and boilers, 229. 
and valve-gear, 226. 
balance. 228. 
double-beat, 228. 
gridiron, 228. 

of steam-engines, how to set. 224. 
relief, 228. 
rotary, 228. 
safety, 465. 
semi-rotary, 228. 
throttle, 228. 

Vapor, diffusion of, 502. 

Vaporization, 502. 

Vapors, 525. 

Variation of the compass, 377. 

Velocity, 610. 

58 * 


Velocity, unit of, 564. 

Vertical air-pump, 354. 

engines, how to balance reciprocating 
anti revolving parts of, 202. 

Visible horizon, 378. 

Volume of steam, 64. 

Vulgar and decimal fractions of an inch, 
table of, 561. 

Walschaert link-motion, 191. 

Wanlvvell’s high-pressure valveless en¬ 
gine, 240. 

Waste, 478. 

in the high-pressure engine, 103. 
in the low-pressure or condensing en¬ 
gine, 104. 

Water, 514. 

consumption, how to calculate theo¬ 
retical rate of, 288. 
space, 462. 

Water-falls, highest, in the world, 500. 

Watertown automatic cut-off engine, 214. 

Wedge, 611. 

Weight, 610. 

and bulk of different substances in 
cubic feet, pounds, and tons, table 
showing, 620. 

of atmosphere per sq. in. correspond¬ 
ing with different heights of barome¬ 
ter, 365. 

(.f boiler-plates 1 foot square and from 
one sixteenth of an inch thick, table 
showing the, 626. 

of castings by weight of patterns, table 
showing, 620. 

of cast-iron balls from 3 to 13 inches in 
diameter, table showing, 624. 
of cast-iron pipes, 1 foot in length, etc., 
table showing the, 627. 
of cast-iron plates per superficial foot 
as per thickness, table showing, 624. 
of different metals per cubic foot, table 
showing, 621. 

of round iron from one-half of an inch 
to 6 inches in diameter, 1 foot long, 
table showing, 625. 

of square bar-iron, from one-lialf of an 
inch to 6 inches square, etc., table 
showing the, 626. 

of water at different temperatures, 
table showing, 520. 
unit of, 563. 

Weights and measures, 610. 









AVells two-piston balance-engine. 232. 
Wetherill Corliss engine, the, 583. 

What indicator.diagrams show, and how 
they show it, 321. 

■Wheel and axle, 611. 
rolling circle of, 398. 

W T heelock automatic, cut-off engine, 214. 
Wheels, fly, 192. 

Whistle.signals, marine, 389. 

White metal, 615; 

Whole-stroke valve-gear, 227. 

■Wind storms, horse-power of, 499. 
Wire-drawing, 268. 


William Sellers & Co.’s injector, 408. 
Wood as fuel, value, compared with, 504. 
Woodruff’ & Beach automatic cut-off 
high-pressure engine, 124. 

AA’ork, 611. 
unit of, 564. 

Wrecking-pump, marine, 359. 
AVright’s automatic cut-off engine, 38. ’ 
AVrist-plate, 229. 

AVrouglit-iron, linear expansion of, 621. 

Zenith distance, 382. 

Zero, 268. 
























































s ,y-' 

v . \ V . S • * 7 


* 3 N 0 ^ 

* * * 0 




~ C> <£. 

>, * * n v ^ 

0 » JL ” *'\ * ' * ft * S . I g *■* 

«, v 1 * k<$ ,A X t 0 N G * O. f 0 v ’ \ , ^ 

** * .iT u * mMfcz* * ^ 





Jl" ■*£- y- 

- V* V • ^ b0' j 

1 A " \>s s * * U "> 3 N A& * ^ ** 

' K S - A» *• 

f> .V. * ft '>C- <1 - <* ,[nO i 

•<C» „'0 - JillS. ' •%• 0 



.0’ >V - saKivfe' » .s' •%(, °,'wjavw , » a’ 

O, ' *1 . s S N .0 <* . y 0 * \ N c 

C 0NC *^O- 1 r 0 V V* «-f » ^ °0 

^ * je/r?^. * ^ a\ - ^ 



r iTS 


*% 


^ V* 


> V 







^TT,»\/ sS ... V*’ N 0 >°\'»»/% *"' 

*- & * €8® - ■%• -V * .ct^y^» % .0 V 



i r^ y> -■=*<»-»--- -s > y 

r\ O^/ s S .0 

s' t «"‘.,V ** f 0* <*' 





^0 ©^ . ■■ ■ ■ 

*»».’■ \"'-'’*'/ 1 s.., *»»» '"/ V » > 

> ,0^ 6 0 A X‘ V r 

'r v' 03 V\Wlft*\y/.' r) * -/if 

^ © fj 

O' ^ C ' “ * >-' - K C ' 

-0‘ s. * ... i Deacidified using the Bookkeeper proce; 





Neutralizing agent: Magnesium Oxide 
Treatment Date: June 2004 


v 

„ C PreservationTechnologie 


\' Of’ - J ' S r A WORLD LEADER IN PAPER PRESERVATI 

• « i 4 * V >.<?<!, 0 N 0 <\V 111 Thomson Park Drive 

V* v - A» 

v. » ft ^ c V , 

V o 



% s % ' 


Cranberry Township, PA 16066 
(724) 779-2111 











©o' 


^ A. 

A tv* c\ ' oP ^ v 

^ * * * o> % * 81 / ^ s V '«A> * 3 M °l^ 

,V» v- - -• « *** s A "' 

^> v //.*) ° 

x v» a: 


« c ^> 

% 

1 > ^ - Sfe' - A <*, 

■2, '<, .c ,0 

' 0 ./o ** .0^ « 1 1 • * 

i^W' . 0 * *3/^ * 






•'/' «?VV ■■ ^ 

' " * * A ON c . °if* »* A 

*3v, ^ v> t, " . O 

'1 *P * .x-S^v . <" 


w 



0 * X 

*„ <fi 

^ X 

^ ^ K 

>° °- 

' Kvsi > 0 0 C c ^1 

Im ° n* ^*°,\- *"' 

I *• £? S) * A 

l ‘ •*»• *- r* 


<V> '^, o 

fi,,t, l \'"''^'; , A , ’ , ‘ 

; «bo< >' <# 



0 kV ^ * 



z * \ 


<* X 


o N 0 ' 

.0 V * 1 * °/- 
A» V- « fe < 

'A -<* - rfp#A 

|>‘ A ^ IPSPI^ c <5» <<. o WWS? * aV </> Z " 

f *>, 0 * V 5 A> , v VJ$ ,\K •* <\v ^ » 

hi.V-''/.'". % 

~ \ /t\ -< r J^ v L c 

* O0 * ^ ^ r 




\ 0c Z<. 




"W 


A 

V s 


’ffAi- * -v. jj- 

/ » 

*C^S a 


>11 

V * n * 1 

^ ' ° A *Cv 

* j ra / " % “ \ / • 

<v> ^ 

* .V ^ ^ 

. O ff i s s \0^ <* •/ „ . . -i 



0 « X 


\ v ' 


y # r\ 


x 00 ^, 



•>* V 

O o N 



) % o 




c5> 

o'* S 


V 


„...„_ -' .<0 ^ 

%, '■•To"*' / .. % '*, ;'o’■ iQ- 

v * 0 /• <£». v X ^ s * ^ 

* o ^ . _ v . A is *. ^ a o 








































